Question about Rt vs simple rate of growth in cases

[jstover79]

I'm just wondering what this gives us that a simple rate of growth in cases doesn't. E.g., the interval ranges seem to be extremely narrow and therefor are not predictive of the future spread. A simple calculation of (total cases today)/(total cases yesterday) seems to be a fairly accurate predictor of case growth over the next few days. I haven't done the calculation, but looking at WA data, this Rt model is out of sync with the actual daily number of total cases. E.g. Rt went high for WA a few days ago, yes actual number of cases has still be growing slowly by about 1-2% a day., lowest of all 50 states except VT.