no growth on Cycas
 

I have a Cycas revoluta "sago palm" (hope houseplants aren't OT ??) which
has shown absolutely no growth whatsoever in the couple of years I've had
it. The only visible change has been that a few of the leaflets have turned
yellow, but most of it is nicely green. It gets moderate water and light
mistings. It's in bright light, some sun, indoors. Will anything stimulate a
bit of growth? (more heat? less heat? more water? drying out?)

Thanks for any suggestions,

Duncan