It will be tough to compare a schedule of weeks ahead, because Flex Daily goes day-by-day to determine whether to water the next day or not. But for the sake of your spreadsheet (which I had to make too, manually entering each day and how much water the schedule said would be applied each day - until I realized the basic premise of operation), here are some formulas for you:
Inches of Water Applied Each Cycle = Root Depth x Available Water x Allowed Depletion
If Root Depth = 6", Available Water = 0.17" (Determined by soil type) and Allowed Depletion = 50%
Inches of Water Applied Each Cycle = 6 x 0.17 x 0.50 = 0.51"
Watering time to apply that water is:
Watering Time, min = 60 x Inches of Water / Nozzle Inches per Hour x Scheduling Factor
Scheduling Factor is based on Efficiency and is:
Scheduling Factor = 1 / (0.4 + 0.6 x Efficiency). For 80% Efficiency, it would be:
Scheduling Factor = 1 / (0.4 + 0.6 x 0.80) = 1 / (0.4 + 0.48) = 1 / 0.88 = 1.1364
Assuming Nozzle Inches per Hour = 0.7 in/hr, continuing with the example:
Watering time for 0.51" = 60 x 0.51 / 0.7 x 1.1364 = 132 minutes or 2:12
The only other calculation that Rachio does it for the Crop Evapotranspiration value for each day, which is a calculation of the amount of water your lawn needs each day. It varies, each day, with the Temperature, Humidity, Wind Speed, Solar Radiation, Hours of Sunlight, and Crop Coefficient (probably more). The only ones you have control over in Rachio are the Hours of Sunlight, and Crop Coefficient.
Right now, where I live in South Carolina, the calculated CEs for each day this week are:
0.12 0.14 0.11 0.13 0.1 0.11 0.1
These total 0.83" for the week, meaning on average, Rachio will apply 0.83" of water this week (less whatever rain we get). This is a cooler, wetter, more humid week than normal; we can have daily CDs close to 0.30, which would apply twice the water. Compared to historic data, this would be a good bit lower than normal, but then so is the current requirement, so that saves water.
The 0.83" for the week (or about 0.12" per day) could also be extrapolated to 0.83" x 30 / 7 = 3.56" for the month, to compare with your information. But again, it’s low right now, so that must be taken into account.
Anyhow, for your Schedule: with Flex Daily, Rachio (or you) can initially “fill” your yard by watering extra to be sure the moisture level in the lawn is at its maximum. Then it will wait, each day, subtracting the value for the CE, and adding any rain received, until the total nears zero (which is your Allowed Depletion). If the next day will be at zero or less, it will water that next day, in this case the 0.51". This is shown VERY well in the Soil Moisture Graph & Chart, and is in itself a reason to use Flex Daily, as this graph only is shown or applies to it.
Another way of looking at the numbers is that it will water 0.51" every 0.51 / 0.12 days or every 4.25 days. So days of schedule (W = watering day, x = no water) might look like: WxxxWxxxWxxxxWxxxWxxx etc. This could be extended over any time, but it’s going to be changed by 1) the rain received, and 2) the change in the daily CE value.
If the total water per week or month is lower than you really think is required, increasing the Crop Coefficient is the best way to adjust this. Total water applied over time is directly proportional to the Crop Coefficient. Or, if you have used a different controller on your zones, compare the TOTAL time that Rachio will water over, say, a week or a month with what your previous system would use.
Hope this helps you to complete your spreadsheet and confirm what Rachio should do during that period of time.