Stupid question - Why do I often see the letter "Z" following a number written in newspaper articles?

At first I thought this was just a typo, but its actually quite frequent (at least 2 times a week), it's not just limited to my local newspaper, and it's always only after a number. For example, "More than 1z 1/4 feet of snow had fallen in the area, authorities said." So is this some stupid new thing they teach in english cl that they hadn't invented yet by the time I graduated from college in '02? It's only recently that I began to notice this. It's a dumb little thing but it's starting to bug me.