One sourced statistic beats three superlatives. This is our maintained reference on legacy modernization — every figure named, dated, and attributed, presented as a range when sources disagree. Last reviewed June 2026.
Each is reproduced as its source stated it. Where two credible sources disagree, we show the range rather than pick a side.
of digital transformations fail to deliver on their objectives.
The base rate for big, all-at-once change programs is failure. Slice-by-slice delivery exists to change which side of this number you land on.
lines of COBOL estimated in production worldwide.
Reuters reported roughly 220 billion lines in production; Micro Focus later put it above 800 billion. Either way, COBOL is not a relic — it is load-bearing infrastructure, and it is not going away on its own.
of developer time is lost to technical debt and bad code.
Nearly half of engineering capacity is spent fighting the codebase rather than building. Modernization is, in part, the work of getting that time back.
of the technology estate's value is technical debt; managing it can free up to 50% more engineering time.
Debt is not just a cost line — it is a tax on every future change. Paying it down is one of the few moves that compounds in your favor.
is the average age of a COBOL developer; about 10% of the COBOL workforce retires each year.
The people who hold the undocumented rules are leaving on a schedule. Capturing that knowledge as living specs is a race against the calendar.
mainframe modernization market, 2025 to 2030, a 9.7% CAGR.
The market is roughly doubling this decade. Modernization has moved from optional to budgeted across the enterprise.
of the IT budget goes to running existing systems rather than new capability.
Most of the IT budget keeps yesterday running — Deloitte surveys put the run-the-business share at 55–57%. Modernization is how that spend gets pointed back at the roadmap.
Figures are reproduced from their original sources for reference and may be revised as those sources update. Spotted an error? Tell us — we correct in place with a dated note.