I know exactly where all my chickens came from.  That's "all," collectively.  Either I bought them as chicks, a few somebodies each gave me one, I incubated and hatched several bunches of them, and broody hens hatched the rest of 'em.  Numbers?  Uhhhhhh.....  
Last night, as I was feeding SOME of them treats (the ones which had gravitated to the front yard), I noticed I have quite a few REALLY PRETTY chickens.  I mean, so many of them are cross-breeds, but I have a LOT of really good looking chickens.  And must admit I have not named quite a few of them....  I usually wait until they demonstrate individuality so their names "come to me" but I have apparently been lax of late.
...and 25 more chicks just arrived today, being fostered by my good friends HHandbasket and Farmer Lew until I get moved to my new home.  There's already 20 chicks, a gosling (Kate), and a nearly mature Porcelain D'Uccle (Gwenevere) at the new property.