All the hens are back online and in fact, this has been a fantastic February with 21 eggs as of yesterday. Not bad for our aging flock of 3 hens. Here's a picture from yesterday, our second three-egg day this month:
Last night a friend visited and showed us a picture of her freshly hatched duckling and that got the whole conversation started about how much longer our current hens (our first hens) will continue to lay and what we'll do afterwards. If we lived someplace outside of the city, we could have ducks and chickens. But here in the suburbs, we can only have three animals (other than "regular" household pets).
One of the several chicken-keeping neighbors in our block stopped keeping chickens recently. They said it was because of the math. They weren't getting enough eggs "to offset the costs." We keep chickens for many reasons, so it's not primarily a math equation for us.
I'm not sure yet what we'll do once they stop laying. I know it's not really a light switch occurrence -- they don't just wake up one morning and go from laying many eggs a week to laying zero. So at some point the gradual decline will become noticeable and we'll have to start buying eggs again. Then we'll decide.