| C_FILE | ADA_FILE | SCRIPT_FILE | OTHER_FILE | TOTALS | |
| all_lines: | 1925523 | 1883751 | 117964 | 604078 | 4531316 |
| SLOC: | 1508695 | 1272771 | 117964 | 604078 | 3503508 |
| files: | 6057 | 9385 | 2815 | 3653 | 21910 |
| updates: | 47775 | 34516 | 12963 | 12189 | 107443 |
| new_features: | 26483 | 23031 | 5594 | 6145 | 61253 |
| Fixes: | 13890 | 5841 | 4603 | 1058 | 25392 |
| Fixes/feature: | 0.52 | 0.25 | 0.82 | 0.17 | 0.41 |
| Fixes/KSLOC: | 9.21 | 4.59 | 39.02 | 1.75 | 7.25 |
| devel_cost: | $15,873,508 | $8,446,812 | $1,814,610 | $2,254,982 | $28,389,856 |
| cost/SLOC: | $10.52 | $6.62 | $15.38 | $3.72 | $8.10 |
| defects: | 1020 | 122 | (A) | (B) | 1242 |
| defects/KSLOC: | 0.676 | 0.096 | (A) | (B) | 0.355 |
The C and Ada areas are worked by about the same people (with a slight advantage to C) and using the same tools under approximately the same conditions.
Source: Stephen Zeigler,
“Comparing Development costs of C and Ada”, 1995
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From the Script: SLIDE 36 - Data for Overall Development of the VADS Product Line
The VADS product line is a set of programming tools sold by Rational Software Corporation. It was originally developed by Verdix, which later merged with Rational. An analysis was performed on the historical software development records as part of the merger. The results were used to determine the value of the companies and also to discover the best practices to continue in the new merged company.
The study was conducted in 1993 through 1994. The results are shown in this table. They provide us with an objective comparison of C and Ada. These statistics were derived from data generated automatically by the software configuration control system. The C and Ada areas are worked by about the same people, using the same tools, under approximately the same conditions. The C programmers enjoyed a slight advantage because they tended to be more experienced.
The conclusion was that C development was more costly than Ada. You will note that the cost per thousand lines-of-code for C is $10.52. For Ada it is $6.62! The defect rate per thousand lines-of-code for C was over seven times the rate for Ada.
Ada code was found to be better organized, because the language encourages better programming. Errors are easier to locate. The programming tools are superior. The increased power of the Ada language was found to make complex programming tasks easier.
From a business and technical standpoint, this study proved that Ada makes more sense than C, and early reports are that C++ is showing even higher error rates. [Zeigler]