In fewer than eight years there will be just one million defined benefit savers in the UK, while defined contribution schemes will cover 16 million workers, the Pensions Policy Institute predicts.
This shift in the structure of UK pensions by 2020 comes as the decline of DB provision accelerates, with just 16% of DB schemes still open to new members this year.
The PPI said the introduction of auto-enrolment will send the number of DC members rocketing upwards from the current 6.6 million members.
The PPI report, sponsored by MetLife Assurance, on changes to private sector provision found that in the 1950s employer and employee would have contributed 11% of a worker's salary to a DB scheme to reach a 1/60th accrual rate with retirement at 65, while in 2012 the cost shot up to 21% of salary due to regulatory changes.
But PPI research director Chris Curry said the existence of open DB schemes - 16% of the total - shows employers may still be interested in risk-sharing.
He said: "We keep saying it is the final nail in the DB coffin, but perhaps the coffin is made of metal not wood.
"Those employers [with DB schemes] might be interested in maintaining risk."
Curry (pictured) pointed to pension minister Steve Webb's much-touted "defined ambition" middle-ground, where employers would take on some risk instead of passing it all to their employees under DC.
He said the government's timetable was "not clear", but he expected any shift to DA to come after auto-enrolment.
MetLife chief executive officer Wayne Daniel said he expected DC schemes would begin adding guarantees that would see them take on the characteristics of a "defined ambition" option.
The report also found a significant shift away from equities and into bonds in DB portfolios. In 2006, 60% of all assets in DB schemes were in equities and 30% in bonds, while in 2011 equities had shrunk to 40% of total assets, with bonds rising to an equal 40%.
Strategies to reduce liabilities or pass them onto insurers have increased since the financial crisis.
Between 2010 and 2011 the total value of liability driven investment under management increased by almost 30% from £243bn to £312bn, while risk-transfer deals such as buyouts reached around £40bn, rising from 0.2% to 2.7% of total liabilities from 2007 to 2011.
Curry said the numbers showed there was scope for further growth in the risk-transfer market as DB liabilities mature depending on affordability and market capacity.
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