Erik,
No, two of my colonies are 1.65 and 0.8751 and my home system the three worlds are 0.0. BUT, I have found the problem. Under the Civilians / Ind Status at the bottom there are three radial buttons: Destination of colonists, Source of Colonists, and Stable. The Source of Colonists was selected so I changed it to stable... The population is now growing....
Thanks for the thought though