X-Ray Apparatus and Tubes and Related Irradiation Apparatus

SIC 3844

Companies in this industry

Industry report:

Firms in this industry engage primarily in manufacturing irradiation apparatus and tubes for applications such as medical diagnostic, medical therapeutic, industrial, research, and scientific evaluation.

Industry Snapshot

The irradiation apparatus manufacturing industry remained robust throughout the first decade of the twenty-first century, declining only slightly during the economic recession of the late years of the first decade of the 2000s. Value of shipments in the industry stood at $6.8 billion in 2010, up from $6.2 billion in 2009 but still below pre-recession levels of $7.0 billion in 2006, according to the U.S. Census Bureau. The industry made positive gains as advances were made in imaging technologies. The increasing sophistication of computed tomography, which was undergoing rapid technological advances, drove growth in the industry. In addition, handheld and portable X-ray devices became more widely used in the offices of doctors, dentists, and veterinarians, as well as having a variety of industrial and manufacturing applications. Furthermore, X-ray equipment had increasingly wider uses as the decade progressed as a method of security against terrorist attacks.

In the early 2010s, approximately 180 U.S. companies were involved in the irradiation apparatus industry, an increase of over 10 percent from the late 1990s. The largest companies (those with more than 500 employees), which accounted for less than 8 percent of all establishments, commanded more than two-thirds of the industry's revenues. Ninety percent of all industry revenues came from establishments with more than 50 employees, which made up about one-third of the establishments in the industry.

Background and Development

The discovery of the X-ray was an accident. In 1895, Wilhelm Conrad Roentgen, experimenting with electrical discharges in an evacuated tube called a Crookes' tube, discovered that the invisible rays given off from his experiment could penetrate a human hand and project a skeletal image onto a florescent screen. Later, he substituted photographic film to make a permanent record. Since then, scientists have discovered that X-rays are a type of electromagnetic radiation. An X-ray's wavelength of 0.01 to 300 angstroms is shorter than visible light, lying between and partially over the ultraviolet and gamma-ray segments of the electromagnetic spectrum. They are produced by the collision of high-energy particles with other charged particles.

U.S. scientist William D. Coolidge developed the first efficient X-ray tube, called a Coolidge tube, in 1913. Modern tubes fire electrons from a tungsten filament cathode at a target anode, usually made of tungsten, molybdenum, or copper and coated with a thin film of gold.

The speed of passage of the X-radiation through a body depended on density. Relatively dense material, like bone, yielded white images, whereas less dense material like lungs appeared black. Doctors found the phenomenon invaluable for accurately diagnosing tuberculosis, miners' black lung, and broken bones, among others. However, it only provided a two-dimensional image of the problem area, superimposing layers of body components one on top of another without any indication of depth. One solution to that problem was to use a contrast medium like liquid barium to highlight the esophagus, stomach, and intestine. By using a fluoroscope, which produced real-time images on a video screen, the physician tracked the medium through the digestive system, pinpointing any problems.

A major advance in the effective use of X-rays for medical diagnosis occurred in the late 1960s. By linking the computer to a moving X-ray emitter inside a doughnut-shaped machine, Geoffrey Hounsfield of EMI produced a three-dimensional image of an entire object. Instead of a few X-ray photographs, the computer-aided-tomograph (CAT) took hundreds of thousands of carefully directed, slice-like images, which the computer reassembled. Tomograph comes from the Greek word for slice. The results were startlingly clear and could be manipulated to highlight specific areas. CAT scans could locate bleeding inside a brain, find and measure tumors, or help to evaluate injuries anywhere in the body.

Concerns over the amount of radiation exposure for a patient along with the cost and sheer physical immensity of the equipment led to the development of ultrasound tomograph, which did not use X-rays. By the mid-1980s, the ultrasound systems began to gain popularity. Ultrasound systems are classified under SIC 3845: Electromedical Apparatus.
Magnetic resonance imaging (MRI) uses a powerful magnet to align the hydrogen atoms in a patient's body. When the magnetic field is released, the atoms return to their original orientation, but different tissues realign at different rates. By using a computer to clock the relative rates of change, physicians can map joints, tumors, and post-surgical changes in the chest, abdomen, pelvis, brain, and spinal cord.

The safety and effectiveness of all medical devices became the responsibility of the Food and Drug Administration in 1938. Radiation emitting devices were specifically targeted in 1968 by the Radiation Control for Health and Safety Act and, in 1976, by the Medical Device Amendments to the Food, Drug, and Cosmetic Act.

In the late 1990s, the continued concern for radiation exposure to patients led to further advances in X-ray equipment development and technological advances. One of the technological advances in 1997, called a "soft" X-ray, was a new technology that used long wavelengths to decrease radiation.

By the 1990s, even though other safer technologies were displacing X-rays in their traditional medical applications, radiation proved useful in unique ways. The fluoroscope could show movement within the body, such as the action of the heart and the intestines. It facilitated angioplasty, providing the physician with a real-time way of guiding a balloon-tipped catheter down a blood vessel to the point where the balloon insert could be expanded with the greatest effect. Radiation oncology used X-rays or gamma-rays to attack cancerous tumors without damaging surrounding tissue. With this technique, a linear accelerator, betatron, or cobalt machine is used to direct a beam of radiation from outside the patient's body at the pinpointed tumor.

Initial investigations of the radiation in the research laboratory led to many useful applications for the non-visible light energy. X-ray crystallography led to X-ray microscopes. Crystal structures direct and control X-rays much as lenses do with normal light energy. Using this principle, researchers were able to delve ever deeper into the structure of crystals. The fact that X-rays are absorbed by material led to absorption spectroscopy, which studies metals in living systems. The industry began to use lithography to produce densely packed computer chips. Holography made it possible to glimpse the world within a living cell.

Scientists also used radiation to look beyond earth. By launching satellites equipped with X-ray detectors, they were able to observe and theorize about the structure of the universe. The first such satellite, UHURU, was launched from a site near Kenya in 1970 and was followed by an international series of successors. Gamma-ray astronomy extended the reach of X-ray astronomy, making visible the processes of the destruction and creation of chemical elements throughout the universe.

Archeology and paleontology also benefited from the use of X-ray technology. Previously, the study of ancient artifacts, such as mummies and fossilized bones, required the systematic destruction, or at least the disassembly, of the scientific treasures. Using a CAT scan, often tied to a supercomputer, researchers could get clear three-dimensional images without reducing the artifact to dust. Such scans often revealed surprising facts about the subject, giving a glimpse of what life, society, disease, nutrition, and intrigue was like in historically distant times.

X-rays also proved invaluable in probing modern-day intrigues. In the 1980s and 1990s, plane hijackings and bombings brought terror to the skies, and advances in weapons technology threatened to make conventional X-ray scanners ineffective in preventing them. Although metals showed up clearly on an X-ray scan, lighter materials like plastics did not. Plastic explosives and the mostly-plastic Glock 17 handgun could be smuggled through security inspections undetected. Specially designed innovations like American Science & Engineering Inc.'s Model Z scanner sought ways to tighten security. The Z-scanner concentrated a high intensity beam of X-rays onto the carry-on luggage to compensate for the low absorption rate of softer materials. It then displayed both the normal X-ray image, which picked up metals, and the Z-image, which caught plastics. In 1991, France extended that technology for use in its massive cargo inspection facility at Paris's Charles de Gaulle airport. The building-size X-ray machine examined entire pallet loads of luggage or entire vehicles at once, producing a sophisticated, easily read image.

By increasing the power and size of the X-ray equipment, industry businesses were able to probe through several feet of metal to map interior details. Defense subcontractors used CAT scans to inspect MX missiles and Saturn rockets looking for cracks, poor material bonds, migration of fuel or coolants, integrity of castings, and gaps in insulation. In traditional CAT scans, the object to be probed sits within the doughnut shaped emitter ring, but in the late 1980s, industry leaders developed a technological innovation called backscatter imaging tomography (BIT). By capturing only the portion of the beams that are reflected back, BIT machinery allowed operators to probe objects even if they could only access one side. The process provided an efficient method for checking the quality of manufactured parts and allowed inspectors to certify and document such critical items as pipe welds in nuclear reactors. X-rays have also been used to examine the nation's highways by detecting early signs of failure and allowing preventative maintenance in place of major periodic rebuilding.

Mergers and acquisitions of X-ray apparatus and tubes companies became popular in the mid- to late 1990s to match the trend in hospital downsizing, the combination of physician offices, changes in managed care, and decreases in insurance availability for medical services.

The terrorist attacks on the United States on September 11, 2001, brought increased attention to X-ray use for passenger luggage screening at airports nationwide. InVision Technologies, one of the two companies certified by the Federal Aviation Administration (FAA) to manufacture bomb-screening machines for luggage, received an order for 100 machines from the federal government in response to a new law that all checked baggage be screened for bombs by the end of 2002. The FAA estimated that more than 2,000 such machines were needed to meet those requirements. U.S. Customs inspectors also used high-tech imaging equipment after September 11 with the purchase of the MobileSearch X-ray truck designed to inspect a variety of cargo. Only 2 percent of U.S. cargo was inspected using the $2 million truck in the mid-2000s, however. Later in the decade, American Science and Engineering (AS&E) came out with the Z Backscatter Van (ZBV), which was capable of detecting organic matter that regular X-rays do not pick up, including explosives and plastic weapons. However, the machine's ability to see into buildings and clothing was raising privacy concerns among some.

Also in the early 2000s, mirroring the trend of the popularity of digital photography, use of filmless radiology systems, which store images electronically, increased. Benefits of filmless radiology included reducing lost or misplaced conventional X-ray films. They also can be viewed online in a large database, allowing multiple users to have access at the same time, unlike conventional film. Additionally, they present potential cost reduction opportunities by negating the need for creating and maintaining conventional film libraries. Filmless radiology is not without its drawbacks, however, including creating technical challenges to hospitals and the initial expense of their costly picture archiving and communication systems.

Other happenings in the industry in the early years of the twenty-first century included General Electric Co.'s launch of Excite, a magnetic resonance imaging technology that increased the speed of MRIs as much as four times the speed of existing models. Quality and efficiency of the diagnostic procedure were also greatly increased. The technology allowed MRIs to produce images of lungs breathing and blood flowing, to shorten exam times, and to be useful in detecting damage from heart attacks and diagnosing stroke victims. The new technology increased the price of an MRI machine by 10 to 20 percent, but GE claimed efficiency rates would counteract that. GE's advanced Signa SP/2 MRI systems were used for surgical and interventional procedures requiring virtually real-time imaging during a procedure. Intra-operative imaging was becoming more practical and useful as well.

Other advances in the field included a robotic X-ray system called ScanRay. Developed in 2002, it could scan the fuselage and wings of a plane for damage. The system also could be used to inspect ships, roads, bridges, and other concrete structures for damage, as well as to detect explosives in buildings. The technology uses a Reverse Geometry X-ray, which creates an information profile culled from images collected from many different angles. The resulting images are sharper and clearer than conventional X-ray images, while also creating a 3-D digital image by the various angles from which the X-ray is taken. Carbon nanotubes (CNTs) also were being explored to create portable medical and industrial X-ray machines with higher imaging resolution.

Nonetheless, the basic design of the X-ray tubes had not changed significantly since Roentgen's work a century earlier. In 2007, a nanotechnology-based field emission X-ray source technology promised fundamental changes in how X-ray radiation is generated and utilized. Developed jointly by industry leader Siemens Medical Solutions and Xintek Inc., which manufactured nanomaterial-based field emission technologies and products, the technology enabled new diagnostic imaging systems with enhanced performance and capabilities. The two companies formed a joint venture, XinRay Systems, to develop a new multipixel X-ray source technology for a broad range of diagnostic imaging applications.

In the mid- to late 2000s, CAT scan equipment was the single largest sector within the X-ray industry, accounting for approximately 25 percent of all X-ray equipment shipment values. Shipments of X-ray devices used in nuclear medicine generated about 15 percent of shipment values. All other medical-related X-ray equipment, including dental, conventional use, and radiation therapy equipment, added another 45 percent to the industry's revenue. Remaining revenue came from industrial and scientific use of X-ray devices, digital radiography, and X-ray tubes and parts and accessories.

On the medical front, the development and use of X-ray devices continued unabated during the mid-2000s. Technology provided rapid advances in design, providing better imaging. Flat-panel X-ray technology also was on the rise. A flat-panel image detector is similar to an LCD screen but works as a receiver rather than a transmitter. It converts X-rays that strike its surface into light and turns the light into electronic data that can be processed by a computer into a high quality digital image. The use of the flat panel makes medical X-ray systems more compact, maneuverable, and portable.

CAT scan technology also was rapidly advancing. Once only able to provide a single slice of an image at a time, by 2002, 16-slice CAT scan devices were on the market, and Siemens Medical Solutions, an industry leader, had 250 64-slice CAT scan machines installed throughout the world--the largest global network of this cutting-edge technology in the mid-2000s. These high-end CAT scan devices provided unprecedented image quality with scan times as short as 10 seconds. Thus, the information provided was greatly improved, while the patient's exposure was reduced. Later in the decade, Johns Hopkins University tested a 320-slice CAT scan device.

The use of CAT scans for diagnosis generated some controversy during the mid-2000s. Some medical professionals bemoaned the overuse of CAT scans as a method of diagnosis in asymptomatic cases. With an average cost running $1,000 for a full-body scan, CAT scans were a source of significant revenue for hospitals, but experts argued that overuse leads to a significant number of false-positive results that add additional expense to investigate. In 2005, radiologist G. Scott Gazelle of the Massachusetts General Hospital in Boston told Science News that the use of CAT screening in patients without symptoms "is causing a drain on the health care system."

Despite an effort to contain health care costs and a BlueCross BlueShield Association report that tagged imaging services as among the fastest growing segments of health care expenditures, the demand for image scanning continued unabated. The rapid advance of technology in imaging devices led to an ever-increasing number of screenings requested by doctors and patients. Imaging services are faster, safer, and able to detect a much wider variety of diseases, creating a positive outlook for imaging services and imaging equipment industries.

According to a report by the Business Communications Company released in March 2005, fluoroscopy held 41 percent of the market for radiation-based therapeutic monitoring equipment, which had an overall value of $687 million in 2004. Ultrasound accounted for the largest market share with 44 percent. CAT scan and MRI equipment followed at a distance. Fluoroscopy was expected to grow slowly, but other sectors were expected to increase at a faster pace, including MRI equipment.

Non-medical use of X-ray equipment also grew during the mid-2000s as concerns over national security continued at the forefront of the political agenda. The aviation security sector was particularly robust as airports and airlines continued to ramp up security. General Electric, already involved in security screening and devices, created a Homeland Security division and purchased the explosive device detector company InVision, which had grown tenfold since 9/11.

Current Conditions

This industry continued to expand into the early 2010s. U.S. exports in this industry were worth $4.0 billion in 2010, whereas imports were valued at $3.5 billion. Overall value of shipments was $6.8 billion that year, with more than $1.2 billion originating from CAT scan equipment. Nuclear medicine equipment accounted for just over $1.0 billion in product shipments, and industrial and scientific X-ray equipment was worth about $537 million. Approximately $2.1 billion in shipments came from other irradiation equipment, including parts and accessories for X-ray equipment.

Unlike many U.S. manufacturing sectors, employment in the production of irradiation equipment increased in the early twenty-first century. According to the U.S. Census Bureau, 14,361 people were employed in the industry in 2009, as compared to 13,891 in 2008. Of all employees, only about 32 percent were production workers, who earned an average of $22.41 an hour.

Industry Leaders

The health care division of Siemens Medical Solutions, a unit of Siemens Corp., the American subsidiary of the German Siemens AG, was one of the industry leaders in the early 2010s. Siemens Medical Solutions produced imaging systems for diagnosis, therapy equipment for treatment, hearing instruments, and critical care and life support systems, as well as a wide array of information technology and data management solutions for hospitals, clinics, and doctors' offices. The firm employed about 13,000 worldwide and reported sales of $9.1 billion in 2006; overall sales for the Siemens Corp. totaled $19.9 billion in 2010.

GE Healthcare made computer-based X-ray and fluoroscopic imaging systems for outpatient clinics, hospitals, and surgical centers. A $17 billion unit of the industrial giant General Electric, GE Healthcare had approximately 46,000 employees in more than 100 countries.

Based in Colorado, Fischer Imaging Corp. made general X-ray systems, as well as X-ray imaging systems, for the detection of breast cancer, including the Mammotest biopsy system and SensoScan digital mammography systems. In 2007, Fischer Medical Technologies completed its acquisition of all of Fischer Imaging's assets related to its X-ray business, including Bloom Stimulator, EPX/SPX and VRAD products. Fischer Medical Technologies was owned and managed by the team that owned and managed Fischer Imaging a decade earlier.

Research and Technology

The uses of X-ray technology and its spin-offs continued to grow in the late 2000s and into the 2010s. Medical advances included such procedures as mammograms, which allowed physicians to detect cancerous tumors in women's breasts before they became apparent by traditional methods. Even so, the technology had its limitations. The relatively dense tissue in younger women's breasts hides developing tumors, resulting in no difference in diagnosis rates for women who received mammograms and those who did not for that age category. At the end of the twentieth century, controversy continued as to when women should be tested for breast cancer and how often they should have a mammogram.

Tomography also has found its way into agriculture to observe harvesting techniques for fruits and vegetables and find out when and why crop damage occurred. The rays showed distribution patterns of pesticides and rates of water absorption by different types of roots and different soil-seed combinations.

Micro-tomography opened the miniature world of ceramics and plastics to the researcher and quality control inspector. By using high-energy sources like synchrotron radiation, industry researchers could analyze the internal structures of rocks and minerals like coal and oil-bearing shales, aiding companies like ExxonMobil in their search for new oil and coal fields. Synchrotron radiation is produced by accelerating particles like electrons to nearly the speed of light within a magnetic field. The result is an intense white light. By channeling that light, researchers can create pencil-thick concentrated beams of x-radiation, ultraviolet, and infrared radiation.

This tunable radiation source could map chemical elements within an object. Exxon used the technology to map other elements found within copper, nickel, and iron. Biomedical researchers used the technology to study calcium and gain more knowledge of the makeup of human bones. Intense X-rays could look within the walls of living cells to study their structure and watch the movements of elements like calcium within a body. However, the individual cells targeted by the X-rays would be killed.

The gamma ray version of the CAT scan is the positron-emission-topography (PET), which measures brain activity. Areas of the brain engaged in thought processes absorb glucose tagged with positron radiation. Decaying positrons give off gamma rays that receptors pick up and translate into a light-and-dark image of the brain. Brains that showed higher IQ levels in standard tests showed less activity than those that scored lower. Researchers theorized that the more intelligent brain was "wired" more efficiently and so used less of its capacity to solve a problem. PET also was used for diagnosing cancer and Alzheimer's disease, and in evaluating epileptic patients. Scientists also have been able to test the areas of the brain for depression, aggression, gender differences, and memory loss using the PET scan.

Another advance also used gamma rays. The single photon emission computed tomograph (SPECT) tracked radioactive isotopes through the body and used a computer to build an image of a metabolic function. It was particularly useful for monitoring heart functions.

In 1999, Hitachi won the Medical Design Excellence Award for its AIRIS II open magnetic resonance imaging system. The unit featured an open air design that is open on four sides, offering greater comfort and access for the patient. Some 650 of these systems were installed in the United States, and 1,700 were installed worldwide. By the start of the second decade of the twenty-first century, several companies were manufacturing open MRI systems.

Terahertz imaging was developed in the 2000s as a less harmful imaging alternative to X-rays. The technology was used to detect abnormalities on the skin, including melanomas, diagnosing blood disorders, and even detecting tooth decay. It also offered non-medical applications that benefited the automotive industry by closely monitoring fuel-burning engines and the food industry by allowing researchers to study food during processing. Using a much lower frequency than X-rays, terahertz waves were supposedly not harmful to the body. Terahertz waves, however, could not completely replace X-rays in all areas, because high water content prevents them from penetrating the body in the same manner. However, for areas such as teeth, this is not a problem. Unlike X-rays, the terahertz rays can even allow experts to image delicate historical books without disturbing them at all, allowing imagers to read words on each individual page.

Another advanced imaging technology being developed was a technique known as diffraction enhanced imaging, which produced a sharper image than conventional X-rays. A crystal between the detector and the object being imaged diffracts rays that have been scattered by the object, discarded by conventional X-ray machines, into the detector. A two-dimensional image is then created by scanning the object and the detector through the beam. The technology allows the detection of spot damage to soft tissue undetected by conventional X-rays. The aerospace and automotive industries were thought to benefit from this technology as a method of nondestructive testing of new materials. In addition, by the later 2000s researchers were experimenting with using the technology for early detection of Alzheimer's disease.

In 2005, the Max Planck Institute for Quantum Optics, the Vienna University of Technology, and the Universities of Wurzburg and Munich developed the first laser-like radiation at X-ray wavelengths, with the shortest pulse ever recorded of 0.1 femtosecond to 100 attoseconds. The breakthrough could eventually lead to practical X-ray applications, which would use less intense beams than current X-ray devices and allow imaging of soft tissue. According to PhysOrg.com, scientists testing the x-ray laser known as the Linac Coherent Light Source (LCLS) found in 2011 that the x-ray radiation it produces is the most coherent ever measured.

Another advance that was gaining wider use was the CAT colonography (CTC), which provides a way for radiologists to examine the colon without running a viewing instrument into the bowel. Unlike a regular colonoscopy, sedation is not necessary, and after the procedure patients can return to normal activities.

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News and information about X-Ray Apparatus and Tubes and Related Irradiation Apparatus

U.S. Average Wages in the High-Tech Industry, 1993-1998.(table)(Industry Trend or Event)(Illustration)(Statistical Data Included)
EDN; December 21, 2000; 700+ words
...Telephone & Telegraph Apparatus $51,113...Accessories Electron Tubes $42,444...Electromedical Equipment X-ray Apparatus & Tubes & Related Irradiation Apparatus $49...AND COMPUTER-RELATED SERVICES Software...Electromedical Equipment X-ray ...
U.S. Employment in the High-Tech Industry, 1993-1999(p).(table)(Industry Trend or Event)(Statistical Data Included)(Illustration)
EDN; December 21, 2000; 700+ words
...Telephone & Telegraph Apparatus $110,596...Accessories Electron Tubes $24,852...Electromedical Equipment X-ray Apparatus & Tubes & Related Irradiation Apparatus $10...AND COMPUTER-RELATED SERVICES Software...Electromedical Equipment X-ray ...
Diagnostic apparatus index leads April increases.(Price Watch)(Illustration)
Hospital Materials Management; June 1, 2004; 700+ words
...Diagnostic apparatus led increases...Diagnostic apparatus 143.6 141...8 128.3 Irradiation apparatus 110.9 110...Catheters, tubes & allied products...35 +2.33 X-ray supplies 95...Cephalosporins and related 99.09 -0...
June PPI for med-surg moves down slightly.(PRICE WATCH)(Producer Price Index )
Hospital Materials Management; August 1, 2005; 700+ words
...was 0.4% for irradiation apparatus, and diagnostic apparatus was down the...GRAPHIC OMITTED] RELATED ARTICLE: Recent...61 Catheters, tubes 101.3 102...19 +0.58 X-ray 96.77 96...Cephalosporins and related 105.22 100...
Med-surg producer price indices down in Nov.(Price Watch)
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...Diagnostic apparatus N/A 140...7 95.5 Irradiation apparatus 111.0 111...Diagnostic apparatus N/A N/A...Catheters, tubes & allied products...19 +0.47 X-ray supplies 94...Cephalosporins and related 101.03...
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Hospital Materials Management; June 1, 2005; 700+ words
...diagnostic apparatus, and none...Diagnostic apparatus 141.2 139...9 93.3 Irradiation apparatus 111.6 111...Catheters, tubes 102.63...41 0.18% X-ray 97.17 1...Cephalosporins and related 103.95...
May PPI up slightly for med-surg products.(Producer Price Index, medical and surgical products)
Hospital Materials Management; July 1, 2005; 700+ words
...diagnostic apparatus, and none...Diagnostic apparatus 141.0 139...7 92.9 Irradiation apparatus 111.2 111...Catheters, tubes 102.63...41 0.18% X-ray 97.17 1...Cephalosporins and related 105.22...
Med-surg indices post slight gains in March.(PRICE WATCH)(medical-surgical)(Illustration)
Hospital Materials Management; May 1, 2005; 700+ words
...diagnostic apparatus, and none...Diagnostic apparatus 141.2 139...9 93.3 Irradiation apparatus 111.6 111...Catheters, tubes 102.63 0...41 0.18% X-ray 97.17 1...Cephalosporins and related 103.95...

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