Less diamond ore generated?

It seems to me like diamond ore generation is lower than usual. From spectatormode I can tell that diamond ore is definetally generated, but in survival multiplayer we didn´t find any diamond-ore so far but lot´s of Lapez (6 veins) and Gold (about15 veins ) and, as usual lots of redstone. Without tools it´s hard to tell if we had just very bad luck.