There is an interesting $T$ dependence in the Hall coefficient [[ando]], as shown in Fig 1.  One can estimate the density of holes, $n_{\rm H}$, from measurements of the Hall coefficient with the formula $R_{\rm H}=1/n_{\rm H}ec$.  The data imply that $n_{\rm H}$ increases with temperature.  The temperature-dependent Hall effect data with the formula [[gorkov]]
$$  n_{\rm H}(x,T) = n_0(x) + n_1(x)e^{-\Delta(x)/T}. $$

As shown in Fig. 2,  the temperature-independent component, $n_0$, is proportional to $x$ for low doping.  The gap $\Delta$ for the thermally-excited carriers is shown in Fig.3; it is quantitatively quite similar to the antinodal *pseudogap* from ARPES measurements.