umm, let me count, I spot clean their cage twice a day, once in the morning and once at night, and there are about 6-7 pee patches on the bedding, big puddles and puddles...lets see, divide that by 2, so in about every 12 hours, I'd get 3.5 pees per chin.
But I think its different with every chin, if they drink more, they'd obviously pee more. Mine drink about 50 ml of water everyday.