This morning we learned that US private payrolls posted another disappointing month in March as the job market continued to slow, and Deutsche Bank analysts warn that order backlog growth at Caterpillar (CAT) - maker of earth movers and construction equipment and global-growth bellwether - appears to be turning negative. Negative backlog growth historically precedes a negative earnings revision cycle by three months, and during these cycles, earnings estimates typically get cut by 45%, and shares fall 40% from the peak. Deutsche explained that while Caterpillar management has done a solid job, the global demand