This is an hard one: 1 million FOR/NEXT loop done inside a function.

[code=thinbasic]
DIM MaxCount AS LONG value 1000000

DIM T1 AS DOUBLE
DIM T2 AS DOUBLE

DIM Message AS STRING
Message = "This program will count " & MaxCount & " times.\n"
Message += "Please press Yes to go on, NO to Stop\n"
DIM lResult AS LONG = MSGBOX(0, Message, %MB_YESNO, "Continue?")
IF lResult <> %IDYES THEN
STOP
END IF

'---Speed up operations a bit
doevents(off)

T1 = TIMER
Counter
T2 = TIMER
MSGBOX 0, "Seconds:" & $tab & $tab & FORMAT$(T2 - T1, "#0.000000")

function Counter() as long
Dim i, j as long
For i = 1 To MaxCount
INCR j
Next
end function
[/code]

Try to change Counter function with something different like:
[code=thinbasic] function Counter() as long
Dim i, j as long
For i = 1 To MaxCount
j = sin(i)
j = cos(i)
Next
end function
[/code]