BS25116A 6-Month T-Bill Auction Results vs Projection

This Opinion post first appeared in my blog here: https://pwlcm.wordpress.com/2025/08/14/bs25116a-6-month-t-bill-auction-results-vs-projection/

Disclaimer: This post is just for educational sharing purposes. Please do your own due diligence on any products mentioned in this post.

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Refer to BS25116A 6-Month T-Bill Yield Projection for the projection:

Yield Premium Projection: Projected Cut-Off Yield = 1.58%, ranging from 1.52% to 1.64%

Polynomial Trendline Projection: Projected Cut-Off Yield = 2.07%, ranging from 1.62% to 2.52%

I deviated from my usual projected yield taken from the Yield Premium Projection, and made a guesstimate of projected yield at 1.77%.

Today (14 August 2025) the auction results for BS25116A was released here: https://www.mas.gov.sg/bonds-and-bills/auctions-and-issuance-calendar/auction-t-bill?issue_code=BS25116A&issue_date=2025-08-19

The actual cut-off yield of BS25116A is 1.59%. It is 18 basis points below my guesstimate of 1.77%, how wrong were I when I made that deviation! If I had stayed with my usual projection based on the Yield Premium Method, the projected yield would have been 1.58%, and the actual yield merely 1 basis point above that.

Lesson learnt, don't depend on my own hunch, but stay with the statistical projection model.