Private equity firms are under increasing pressure to spend the record amount of idle capital they have amassed, but the number of well-priced desirable investment opportunities is dwindling.

Dry powder, the amount of unspent capital the private equity industry has at its disposal, reached $822 billion globally at the end of December 2016, the highest on record, according to data provider Preqin -  up from $755 billion a year earlier and $527 billion a decade ago.