Srinivasan Vaidyanathan
Analyst
Yes, sir. It will come over time. But as we keep adding more and more new branches, one weighs the other. But if you look at two years ago branches, very important that you touched upon, if you look at what we opened about two years ago and look at that cohort, and when we look at that cohort of branches about how they are performing, right, our model shows that it should breakeven in two years' time and about 90%-plus, slightly above 90% of the branches have broken even in about 20 months, 21 months. We have another 10% of the branches to breakeven. And when that does, that's the average of, call it, 22 months to 24 months breakeven. So, they are all following their scripted model in terms of how they deliver. We are confident that all of them starts to payback sooner, but we continue to add branches, right. That's why when you see, part of the cost is when there is a credit opportunity, credit costs, as you heard us talk, it's about 49 basis points. And if you look back, what is the -- how does it -- where does it revert to mean, right? At what levels does it revert to mean at some point in time? Call it, 80 basis points, 90 basis points, or in the pre-mortgage book, we would have said that it is 90 basis points, 100 basis points is the mean where it can revert over a period of time whenever that normalizes -- benign conditions normalize. Maybe with the mortgage in, it is more closer to the 80 basis points or something reversion to mean. But the point to mention to you is that for every 10 basis points of credit cost opportunity that we take from a timing point of view, right, within the return framework, ROA framework, we take this opportunity on a timing to invest, it's about 1% to 2% of cost to income that gets invested there, and so that is what. And here we are trying to say as we make those investments, it should start to pay back. So, we can now look at those ones which are more than two years old and those cohorts are performing well, and we now starting to look at the last 12 months cohorts and we will keep tracking them as we go.