From the Air Force Historical Center;
http://www.afhra.af.mil/timelines/index.aspTable 119- AIRBORNE AND EFFECTIVE COMBAT SORTIES FLOWN IN EUROPEAN THEATER OF OPERATIONS, BY TYPE OF AIRPLANE: AUG 1942 TO MAY 1945
Total effective Heavy Bomber sorties from Aug 42 - May 45 =
274,921Table 125- AIRBORNE AND EFFECTIVE COMBAT SORTIES FLOWN BY TWENTIETH AIR FORCE, BY TYPE OF AIRPLANE: JUN 1944 TO AUG 1945
Total effective Very Heavy Bomber sorties from Jun 44 to Aug 45 =
29,153As an alternative comparison, Heavy Bombers dropped a total of 714,719 tons of bombs in the ETO in 34 months (21,021 tons per month average). Very Heavy Bombers dropped 169,676 tons of bombs in 15 months (11,312 tons per month average).