The San Jose Mercury News reported its spring circulation numbers Monday, two weeks after most other daily newspapers did, and the filing shows that the Knight Ridder paper experienced one of the biggest circ drops in the industry. For the six-month period ending March 2005, daily circ at the Mercury News declined 7.1%, or 19,890, to 259,649 copies. Sunday circ fell 9.9%, or 30,793, to 277,632 copies.