My gun buying frequency depends on what crosses my path that interests me.
The last year has been real hard on my wallet. Two S&W .44 magnums, Colt New Service, Colt Detective Special, Colt 1911, Two Ruger single actions, Two Rock Island .45's, two Springfield '03's, a Remington '03 and '03-A3, a Smith-Corona '03-A3, a Winchester 1897 Trench Gun, a Winchester M1917 and an AR15.
I'm not married, my family is grown and gone and when I retire next year I know that there will be very little disposable income to acquire new guns. Most of the money I have used to buy new guns comes from selling things I am no longer interested in or have no further use for.