The Ngiti are an ethnic group of the Democratic Republic of the Congo. Traditional Ngiti numbers were based on thirty-two with a sub-base of four. While this number system has largely fallen out of use and is at risk of disappearing, the Ngiti traditionally used it to count bridewealth, money and commodities that a groom’s family pays to the bride’s parents for the value of a woman to bear his children. Like systems of numbers based on counting cowries (as for example, the Yoruba and Igbo number systems), Ngiti numbers adjust bundles by accumulating (adding to a lower bundle) and back-counting (subtracting from a higher bundle). Accumulating, the most common strategy, is found in almost all number systems. Back-counting is much less frequent, as fewer number systems include it. Unusually, Ngiti numbers use a third strategy known as over-counting, which anticipates the completion of the set that intermediates between lower and higher bundles. Over-counting is relatively rare, found in only a handful of number systems: besides Ngiti, number systems that use over-counting include Kakoli (Papua New Guinea), Old Norse (Scandinavia), and Old Tagalog (the Philippines).