Statisics on the B-29 as published in
a 40th Bomb Group Association Newsletter

"A B-29 required: 23,652 pounds of aluminum, 11,308 extrusions, 1,418 forgings, and 618 castings.
The B-29 program was the most complex joint production undertaking of the war.
Average flyaway price was $639,188.
Forget the number of valves swallowed, the number of cracked exhaust stack collector rings, the number of runaway props. B-29's flew 120 hours a month. The 8th Air Force, at its peak, was allowing 30 hours a month in B-17's and B-24's.
A total of 656,600 tons of bombs were dropped on Jap targets. 160,800 tons fell on Japan. All but 13,800 of those tons were dropped by B-29's (7,000 tons by other Air Force units, 6,800 tons by the Navy).
In the period May to August, 1945. an average of 34,000 tons of bombs per month were dropped on Jap targets by B-29's. 175 square miles of urban areas in 66 cities were destroyed. One wing of B-29's in the XXI Bomber Command was dedicated to dropping mines. They laid 12,000 mines in Jap ports, harbors and sea lanes.
Of 5,000 American crew men lost in combat with Japan, only 200 were ultimately rescued from Jap prison camps."