The amounts invested by the ecclesiastical corporations are difficult to ascertain. The examples of loans given in the preceding chapters are only a few of the many thousands contained in the Church records which clearly reveal that the total capital invested by way of personal loans amounted to several millions of pesos. Numerous calculations have been made of the total wealth of the Church in Mexico but most of these estimates are unreliable because of bias, and none seems to have been based on primary sources. Cuevas has indicated the inaccuracies of those most frequently quoted. For example, with regard to Alamán, who stated that the Church owned at least half the real estate in the country, Cuevas points out that according to Alamán's own statistics, the total capital value of real estate was in the region of 4,000 million pesos and that no one had dared to say that the clergy owned 2,000 million pesos worth of land. Such an estimate was clearly incorrect. Again the estimates made by the liberal Mora come under Cuevas's scrutiny. He rightly notes several basic errors, for example Mora calculated the tithe revenue on the basis of the 1829 returns and ignored the fact that since the 1833 law, the yield had greatly decreased. He also ignores the fact that more than half the tithe product was paid to the civil authorities.