Exclusive \jpsi photoproduction cross section off protons measured as a function of the centre-of-mass energy of the photon--proton system \Wgp by ALICE in \pPb UPCs and compared with previous measurements  and with next-to-leading-order JMRT  and CCT  models. The power-law fit to the ALICE data is also shown. The uncertainties of the data points are the quadratic sum of the statistical and systematic uncertainties.