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 .
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