  We use a scalable optical technique to characterize more than 21000 circular
nanomechanical devices made out of suspended single- and double-layer graphene
on cavities with different diameters ($D$) and depths ($g$). To maximize the
contrast between suspended and broken membranes we used a model for selecting
the optimal color filter. The method enables parallel and automatized image
processing for yield statistics. We find the survival probability to be
correlated to a structural mechanics scaling parameter given by $D^4/g^3$.
Moreover, we extract a median adhesion energy of $\Gamma =$ 0.9 J/m$^2$ between
the membrane and the native SiO$_2$ at the bottom of the cavities.
