The Schrade records were not lost. But their production accounting methods changed over the years. And there is not a seperate accounting of individual knives shipped in displays and assortments to dealers. Some large merchants had their own stock number used and there is no key to those numbers. Also for many years they were sold with other knives in gift sets. These are accounted seperately. Here is a cursory reading of a few years of the records for year end shipping on the 34OT pattern.
1969 - 62,647 + 28,024 + 9,595
1970 - 65,338 + 20,821 + 14,128
1971 - 86,185 + 21,293 +14,251
1972 - 141,838 + 14,794 (Sears) + 20,006 (unk)
Of course sales only multiplied after the Schrade Walden years as Schrade grew with the knife market.
1985 - 294,776 + 2,256 + 14,236 +22,901 (SGS-1)
Many special customers at this point are counted with cryptic pattern numbers.
2003 - 256,200
So that gives you an idea of sales quantities. If sales averaged 300,000 for 20 years, 1984-2004, that alone is six million knives. If the previous 20 years of production averaged 150,000 that is another three million. So nine million is a very conservative estimate. It is more likely over ten million or more.
If anyone would like to pay me to go over the complete record I will do so. It will take me the better part of a week to get full numbers as best can be deciphered.