Comparing and Copying Values Between Dates

Ok, not the most efficient code but try this. I don't get exactly the same results as your sample. I get 1.4672 in T6 and 1.5011 in R13. Please check whether the error is in your example or the macro.

Sub x()

Dim rCell As Range, rng As Range, r1 As Range

Set r1 = Range("A4")
For Each rCell In Range("K4", Range("K4").End(xlDown))
    Do Until r1 >= rCell
        Set r1 = r1.Offset(1)
    Loop
    Set rng = r1
    Do While rng <= rCell.Offset(1)
        ' Q
        If Abs(rng.Offset(, 1) - rCell.Offset(, 2)) <= 0.001 Then rng.Offset(, 16) = rng.Offset(, 1)
        If Abs(rng.Offset(, 2) - rCell.Offset(, 2)) <= 0.001 Then rng.Offset(, 16) = rng.Offset(, 2)
        If Abs(rng.Offset(, 3) - rCell.Offset(, 2)) <= 0.001 Then rng.Offset(, 16) = rng.Offset(, 3)
        ' R
        If Abs(rng.Offset(, 1) - rCell.Offset(, 1)) <= 0.001 Then rng.Offset(, 17) = rng.Offset(, 1)
        If Abs(rng.Offset(, 2) - rCell.Offset(, 1)) <= 0.001 Then rng.Offset(, 17) = rng.Offset(, 2)
        If Abs(rng.Offset(, 3) - rCell.Offset(, 1)) <= 0.001 Then rng.Offset(, 17) = rng.Offset(, 3)
        If Abs(rng.Offset(, 4) - rCell.Offset(, 1)) <= 0.001 Then rng.Offset(, 17) = rng.Offset(, 4)
        ' S
        If Abs(rng.Offset(, 6) - rCell.Offset(, 3)) <= 0.001 Then rng.Offset(, 18) = rng.Offset(, 6)
        If Abs(rng.Offset(, 7) - rCell.Offset(, 3)) <= 0.001 Then rng.Offset(, 18) = rng.Offset(, 7)
        If Abs(rng.Offset(, 8) - rCell.Offset(, 3)) <= 0.001 Then rng.Offset(, 18) = rng.Offset(, 8)
        ' T
        If Abs(rng.Offset(, 5) - rCell.Offset(, 4)) <= 0.001 Then rng.Offset(, 19) = rng.Offset(, 5)
        If Abs(rng.Offset(, 6) - rCell.Offset(, 4)) <= 0.001 Then rng.Offset(, 19) = rng.Offset(, 6)
        If Abs(rng.Offset(, 7) - rCell.Offset(, 4)) <= 0.001 Then rng.Offset(, 19) = rng.Offset(, 7)
        If Abs(rng.Offset(, 8) - rCell.Offset(, 4)) <= 0.001 Then rng.Offset(, 19) = rng.Offset(, 8)
                
        Set rng = rng.Offset(1)
    Loop
    Set r1 = rng
Next rCell

End Sub