A “number cruncher” (also “number-cruncher”) was originally a computer that can process raw data and produce reports. This definition has been cited in print since at least 1966.
 
“Number cruncher” also means an accountant or statistician who can process numbers. This definition has been cited in print since at least 1971. A similar term to “number cruncher” is “bean counter.”
 
 
(Oxford English Dictionary)
number cruncher, n.
colloq.
1. A computer or software capable of performing rapid calculations with large amounts of data.
1966 New Scientist 29 Sept. 729/1   The Flowers report recommended the setting up of some ‘regional centres’ each with a large ‘number-cruncher’ to take the bulk-computing load off more local machines.
2. Freq. derogatory. A statistician, accountant, or other person whose job involves dealing with large amounts of numerical data.
1971 A. Sampson New Anat. Brit. v. xxvi. 497   Kenneth Keith, a brusque number-cruncher who had come into banking from accountancy.
 
Google Books
New Scientist
Volume 31
1966
Pg. 384:
The idea is to unite a dedicated monolithic number-cruncher with a multi-access machine which can prepare and load on the number-cruncher the large jobs for which it is strikingly efficient, and itself handle the small jobs that would be expensive and disruptive on the number-cruncher, and provide numerous widely scattered terminals allowing equivalent access—apart from line-cost—from an office at, say, University College London and Southampton.
 
Google Books
The Statist: A Journal of Practical Finance and Trade
Volume 190
1966
Pg, 289:
BUSINESS COMPUTERS BATTLE OF THE GIANT NUMBER CRUNCHERS
The race to build the world’s largest computer is apparently more than just status seeking. The commercial potential seems to be very worthwhile, too, reports science correspondent PETER STONE.
 
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The Design of Information-Processing Systems for Government
By James H. Robertson
London: Her Majestyś Stationery Office
1967
Pg. 10:
Computers of the first type have had powerful input/output facilities with a less high-powered central processing unit. The second, now coming to be known as ‘number crunchers’, have had a very powerful central processing unit with less high-powered input/output facilities.
 
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25 January 1972, Princeton Alumni Weekly, pg. 13, col. 1:
Still, the image of Bowen as an implacably rational, cost-accounting technocrat (a “hard-nosed number-cruncher,” in the words of one student who says he personally disagrees with the image) remains to be reckoned with.
 
OCLC WorldCat record
NUMBER CRUNCHER: A Complete Statistical Package for Microcomputers
Author: Jerry L Hintze
Edition/Format:   Article : English
Publication: The American Statistician, v36 n4 (Nov., 1982): 386
Database: Mathematics & Statistics
Other Databases: JSTOR
 
OCLC WorldCat record
Careers for number crunchers & other quantitative types
Author: Rebecca E Burnett
Publisher: Lincolnwood, Ill., USA : VGM Career Horizons, ©1993.
Edition/Format:   eBook : Document : English