the new MAP rit scales can be found in this link

http://www.nwea.org/sites/www.nwea.org/files/resources/NWEA_2011_RIT_Scale_Norms.pdf

Are you sure he took MAP already? The winter MAP window opens at the end of the month (so I thought). They have 4 testing windows fall, winter, spring and summer (not commonly used).

The percentiles can go down even when there is growth. The norm group had more growth then your ds. I would ask for the NWEA report. It will show you the district average and the national average.