The study also claimed that the average home mover loan was 2.96 times their income, while those buying their first home took out products which were typically 3.3 times bigger.
Michael Coogan, director-general of the CML, said: "There has been a resurgence of fixed-rate lending as borrowers are seeking certainty.
"This trend is likely to continue as the anticipation of future Bank base rate cuts has diminished."
Earlier this week, the CML revealed plans to introduce a new valuation process for newly-built properties in the UK.
Created through consultation with house builders and surveyors, the new system is to be launched in September.
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