Hi there.
Some chickens have randomly laid eggs into their 10th year of life!
Overall things that matter start with genetics, followed by nutrition, daylight, and other factors.
Many chickens will easily lay eggs into their 4th and 5th year.. but all will usually take a winter break during which time they molt out and grow in new feathers. To combat this lull in eggs I add in a couple pullets each year and sell off a couple older gals.
All chickens are hatched with every egg they will ever produce already on board.
Laying hormone is light induced.. some folks provide extra lighting, but season definitely effects production. I go natural.. but with 5 hens (depending on age and breed) I would EXPECT them to meet the needs of you and your hubby at LEAST.
OE.. you'd be lucky to get 3 eggs a week at maturity.
Take note of any angry skin indicating parasites. Consider getting a group fecal float to get a look at internal parasite load. Both things can effect production. Also be aware of any possible hidden nest or egg thief.