IN10Y(10yr yield t- bill) are govt. backed bonds provide basic interest or coupon rate. If the coupon rate falls below (yield =(1/price) the coupon rates of 3 month bond IN03MY(3m yield t- bill), investors are pessimistic about future growth of the economy. This pessimistic behavior can be seen in the graph when change in background color. While optimistic behavior scenario when investors no longer interested in long-term bonds and dumping 10Y T-bills causing yields to raise above short term 3m T-bill .
Thanks so much for this! A simple yield spread...all I needed. I modified your code a bit to include the US10Y-US02Y instead of the Indian data which is more applicable to me. Also changed the background color to trigger at 30bp instead of 0. But it was super simple to do thanks to your work. Cheers.