Astroclimatology of ESO Sites	ESO WIDE REVIEW M. Sarazin, April 2000, 1/10

Statistics of photometric nights at Paranal (line) and La Silla (dashes) since the beginning of the VLT site survey. Data is collected from visual observations at Paranal and extracted from the telescope observing logs at La Silla. A photometric night must have at least 6 consecutive hours with a cloudless sky down to 18 degrees above horizon.