The number of global investors with $1 billion or more invested in hedge funds has climbed to a total of 227 over the last year, even as a number of high-profile pension funds withdrew from the space.

Over the past 12 months, 51 new investors joined the "$1 billion club" -- or the group of institutional investors that have put at least $1 billion of their cash to work in hedge funds -- new data compiled for CNBC from alternative asset research firm Preqin showed.