Transit signal strength versus r′ magnitude of detected planetary and binary candidates for the previous IRa01, SRc01, LRc01 CoRoT runs (asterisks), LRa01 run (filled circles), and first seven CoRoT-planets (open circles). D is the transit depth and n is the number of points in a transit event. The horizontal dashed lines represent (from top to bottom) the expected signal produced by a Jupiter-size planet, a Neptune-size planet, and a two-Earth radii planet around a solar-like star, respectively. Transit candidates and binaries were combined in this example to have a better statistical basis of the detection efficiency. The solid line represents the photon noise.