The Blackstone Group continues to reap profits from improving real estate markets.  The investment firm reported a 58 percent jump in its first-quarter  and earnings of $568.1 million in the quarter, atop $1.2 billion in revenue. Its assets under management swelled 43 percent, to $150 billion.

Blackstone earned $43 million, a big swing from the $121 million it lost during the same time last year.

Private equity firms’ fortunes have risen dramatically over the past year as the stock and credit markets stay strong, both bolstering the value of their existing holdings and making financing for new acquisitions readily available.

Steady equity markets have also opened the window for initial public offerings, allowing these firms to sell off their portfolio companies and realize profits. Blackstone has already held offerings for the likes of Nielsen and plans more stock sales, including those for Vanguard Health and Freescale Semiconductor.

Shares in Blackstone have risen nearly 29 percent over the last 12 months, closing on Wednesday at $19. (That remains well below the firm’s initial public offering price of $31 a share.) [NY Times 4/21/11]