The astonishing drop in Philadelphia's prison population over the last year has provided the lone bright spot in this year's city budget. An in-depth 2006 study by Temple University researchers noted that the population exploded from 5,026 in 1995 to 8,541 in 2005, a 70 percent increase. And it only went up from there. But John Goldkamp, chairman of Temple University's Department of Criminal Justice and lead author of the 2006 study, was wary of declaring any victories. "Any developments that have gotten us to reduce the population from its extraordinary highs of the last year or so are good and helpful and need to be institutionalized," said Goldkamp. "It's a good opportunity to make the adjustments that can be put in place in anticipation of more difficult days ahead."