Complex sentence: On the specific issue of Ma'ale Adumim, Peace Now updated the figures for the proportion built on privately owned Palestinian land from 86%, to 0.5%.
Split into simpler sentences: On the specific issue of Ma'ale Adumim, Peace Now later released a report with vastly reduced numbers than it had previously claimed. The estimate of the proportion built on privately owned Palestinian land was reduced from 86%, to 0.5%.