Vatican City, May 13 - The number of Catholics across the globe increased slightly between 2010 and 2011, rising from 1,196 million to 1,212 million, the Vatican press office said on Monday. Figures from the Holy See's 2013 Pontifical Yearbook presented to Pope Francis said that the 1.5% increase brought the 2012 percentage of the Catholics to 17.5% of the world's population. The growth was only slightly higher than that of the Earth's population increase at 1.23%. The number of priests grew 7.5%, largely thanks to a rise of clergy in Asia and Africa, offsetting the 9% decline in Europe over the last decade. The yearbook figures looked at data preceding Pope Francis' election.