Snip from the article.
"Using bullet purchase records between Jan. 16, 2008 through June 1, 2009, Sacramento police found that 151 ex-felons had bought ammunition. Of those, 15 were known gang members, four sex offenders and two spent time behind bars for murder."
"State officials say they have no statistics on ammunition sales because they don’t need to be recorded under current law."
If there are no statistics, where did Sacramento police get this information.