screen altitude warning changing from yellow to red when the  aircraft is descending through one thousand feet, but shows it  changing back from red to yellow at five hundred feet when the  aircraft climbs.  The controllers display shows numerous aircraft altitude readouts  displayed down to the foot, e.g. DMA 134 is shown at 9719 feet.  Controllers readouts show the altitudes only down to the hundreds of  feet. Thus 9719 would be shown as ninety