JW would have been 28 years old today.
The term RIT score is short for Rasch Unit, a scoring scale named for Georg Rasch, a Danish mathematician. The scale is continuous from 0 to infinity (most scores range in the 150 to 300 range) with equal intervals between score points across the full range. The continuous scale means that a student who improves by 10 points between 3rd and 4th grades (moving from 204 to 214) has improved just the same as a student who improves by 10 points between 5th and 6th grades (moving from 219 to 229).
Testing Glossary (http://www.4j.lane.edu/instruction/testingglossary)