Formatting to display 15 significant digits was not intended to "resolve" the problem. It was intended to __reveal__ the problem; at least, provide some insight. Maybe. The point is: perhaps what *appears* to be 143.264 is *actually* 143.2635 or 143.26449. Don't read that literally. That is just an example; wild speculation.

In any case, you do not provide sufficient information for me to help you, as I requested. K5:O5 is only 5 values. Why not provide them all? And be sure to show them (including H12) with 13 or more decimal places.

Why do you think the median should be 144.395? MEDIAN(143,146) = 144.5, not 144.395. MEDIAN(143,145) = 144, not 144.395. MEDIAN(143.264,145.689) = 144.4765, not 144.395. So surely you do not mean that they are the *only* values in the cells K5:O5.

Enter =MEDIAN(K5:O5) into a cell. What does it return? (With 13 or more decimal places.) Or use the Formulas > Evaluate Formula feature to see those values (maybe).

(Unfortunately, sometimes the Evaluate Formula feature does not show all the intermediate steps and values.)