I invested a decent amount of money in advertising on day one only to see my CI actually drop into the negatives over the first few days. I realized however that this was because I went for the cheapest possible planes in my chosen fleet type and most of them were in bad shape until their C Checks came around. Are your planes in poor condition? If so, they'll have more delays and cancellations and it could really hurt your CI especially early on. My own CI has been rising at a reasonable rate now that most of the fleet has received long term maintenance.