Investors began to wrap their minds around startlingly huge job losses on Wednesday, as three research groups provided a preview of what an official jobs report may show later in the week. The high-profile ADP employment report indicated that the private workforce cut 697,000 jobs in February, and upwardly revised its January job loss figure by 92,000 additional payrolls. On the heels of ADP's report came another from TrimTabs Investment Research, painting an even bleaker employment picture, with 778,000 jobs slashed from the private sector. Those whopping figures were much higher than a median estimate of 610,000 job cuts, according to a poll of 23 economists conducted by Thomson Reuters. TrimTabs' report even topped the highest expectations, which ranged from a cut of 500,000 jobs to 730,000 jobs. This year's job losses have been the highest in ADP's records since the firm started keeping track in 2001. The last time the U.S. workforce contracted by more than 600,000 jobs in a month was in 1974, according to the Labor Department. The dismal news may be a preview of the government nonfarm payroll and unemployment report set to be released by the Bureau of Labor Statistics on Friday. The ADP, TrimTabs and government reports include workers who voluntarily leave the workforce, retirements, firings that weren't part of a mass layoff and temporary workers whose assignments have ended. Another outlet, the outplacement consulting firm Challenger, Gray & Christmas, tracks only mass layoffs, and reports that employers fired 186,350 workers last month.