Forwarded from Burt Grad, who for some reason is having trouble sending from his own account and having the list accept it. Tom From: Burtgrad@aol.com [mailto:Burtgrad@aol.com] Sent: Wednesday, September 15, 2010 6:59 AM To: members@sigcis.org Cc: thaigh@acm.org Subject: Petroleum and computers As a developer at IBM's Data Processing Division during the 1960's, I was involved in applications work with many of the major users of mainframes. So far, all of the comments I have read seem substantially correct. However, there was a large gap in the types of companies which were doing scientific/technical computations and those doing business applications. The heaviest business users were banks, insurance companies and manufacturing companies (including aerospace and petroleum/gas). The largest scientific users were the aerospace and petroleum companies. Before the S/360 was announced, I believe that the sales of commercial machines exceeded the sale of scientific machines (certainly in the US); and I believe that the ratio of business to scientific usage was around 4 to 1. Share and Guide may have some data on this and there must have been data submitted to the government in the anti-trust suit which stipulated the sales of various sizes and types of IBM computers during the 1960s. I know that IBM would have been unable to sell S/360s to the Petroleum companies unless we had high functioning LP codes. And IBM couldn't have sold to the Aerospace companies without PERT programs. The only other evidence that I can recall was that by the end of the 1960s a number of the aerospace companies were selling excess capacity on a timesharing and remote processing services basis; some of the petroleum companies also did this but I believe to a lesser degree. Still, in terms of total value of computers sold, I believe that the commercial usage was much greater and therefore the sales to businesses other than Aerospace and Petroleum was probably much greater. Without statistics available to me, I would guess that dicrete manufacturing (not process), banking and insurance were the largest markets (other than government) in the 1960s and probably through the 1970s at least. Burt Grad [co-chair, Software Industry Special Interest Group at the Computer History Museum]