Wischmeyer and Smith published on the USLE, including R factor. Hopefully the methods explained in enough detail the rainfall data needed to estimate. In USA, there is a R factor map which is often used t o estimate this value. The value is based on an average year, and I do not know how many years of storm rainfall intensity data might he needed to estimate. I think they suggested any intensity over 3 inches per hour Maximized erosion. There are a number of assumptions in applying RUSLE, and the L, C and P factors take some measurement or validation. In my opinion, it is typically best to use this as an estimate of erosion, and useful for comparing alternatives or estimating erosion hazard zones, such as when applied in GIS. In SE USA, Dissmeyer and Stump 1978 published a good report on various logging, site prep, road, burning practices on various physiographic areas that might be interesting for you. It is really hard to find updated C and P data as practices have changed. I typically have used Roehl (1962) to estimate sediment delivery ratio for perennial streams (typically 3rd order drainages is what I have used at 1;24,000 scale. An example in Researchgate was the Loblolly Pine Removal Proposal ((2013) that used RUSLE to estimate erosion and compare alternatives.

Hello

USLE, MUSLE RUSLE equations have been used since we did not have computers, automatic weather stations and other measuring devices. Its calculation is very inaccurate and the same applies to the R factor. It gives us information about something average per year, month. The result is not real soil yield but some potential.

Erosion is a huge problem. We almost lose a lot of rare soil every day, and we just count how much it was. And there is an end. We know we've lost tons of soil. Measures against other losses are rarely applied. We have full canals and reservoirs full of soils, but we call it sediments. What is the difference between soil and sediment. The soil has the owner, the sediment is in the river or the reservoir. The soil is composed of soil particles, the sediment is formed by soil particles removed. It's the same we just use two names. R factor is very different in each country. So the soil loss is also different. Today, however, we have to work more practically than with methods 50 years old