goodwrench service mechandising parts

Need some help...
I get a report from my parts reps stating our GSMP purchases are down 59% for the year. I ask them 'just what is a GSMP and how would I know from my inventory which part is in the group'? Get mixed messages: 'It's your fast moving parts' is one response. We have a lot of fast moving parts.
Our dept. sales YTD are up about 10% so our dreaded 'outside' purchases is filling the difference. GM wants us to buy from them, not AC-Delco.
Question: is there a specific definition to GMSP stuff or does it change. One thing, this year AC Delco is selling a/c compressors that were only available from GM.
thanx for the help
scott
I get a report from my parts reps stating our GSMP purchases are down 59% for the year. I ask them 'just what is a GSMP and how would I know from my inventory which part is in the group'? Get mixed messages: 'It's your fast moving parts' is one response. We have a lot of fast moving parts.
Our dept. sales YTD are up about 10% so our dreaded 'outside' purchases is filling the difference. GM wants us to buy from them, not AC-Delco.
Question: is there a specific definition to GMSP stuff or does it change. One thing, this year AC Delco is selling a/c compressors that were only available from GM.
thanx for the help
scott