Thanks - With your help and Sergey I was able to solve my problem.

Gaylen

>>I have a cross tab of production by week based on daily production reports. I originaly had the first column to be weeks indentified as 1,2,3 etc. The client wants the first column to be "Week Beginning Date". Is there a simple way to convert the week to display the first day of that week?
>>
>>Thanks
>>Gaylen
>
>Gaylen,
>
>Having assigned week numbers means that you have defined what the first day of the first week of that year is (see help about week())
>
>date(first day of week(n)) = date(first day of week(1)) + 7 * ( n - 1)
>
>I am including some iso things about dates which you may find useful (don't remember from where I picked it up)
>
>

>The ISO 8601 rule is: The first week of the year is the week containing the first Thursday
>
>
>Algorithm Conventions:
>   "/" = integer division, discard remainder  (5/2 = 2)
>   "%" = modulus, keep only remainder    (5%2 = 1)
>   "&" = concatenation   ("W" & 12 = "W12")
>   "!=" = unequal   (7 != 8  is true)
>   "+=" = add right value to left variable,
>             if F = 3, then (F += 4) yields F = 7
>   "-=" = subtract right value from left variable
>
>1. Convert input to Y M D
>   Y = Year     (full specification; input 98 = year 0098)
>   M = Month    (1 through 12)
>   D = Day      (1 through 31)
>2. Find if Y is LeapYear
>   if (Y % 4 = 0  and  Y % 100 != 0) or Y % 400 = 0
>      then
>         Y is LeapYear
>      else
>         Y is not LeapYear
>3. Find if Y-1 is LeapYear
>4. Find the DayOfYearNumber for Y M D
>   Mnth[1] = 0    Mnth[4] = 90    Mnth[7] = 181   Mnth[10] = 273
>   Mnth[2] = 31   Mnth[5] = 120   Mnth[8] = 212   Mnth[11] = 304
>   Mnth[3] = 59   Mnth[6] = 151   Mnth[9] = 243   Mnth[12] = 334
>   DayOfYearNumber = D + Mnth[M]
>   if Y is LeapYear and M > 2
>      then
>         DayOfYearNumber += 1
>5. Find the Jan1Weekday for Y (Monday=1, Sunday=7)
>   YY = (Y-1) % 100
>   C = (Y-1) - YY
>   G = YY + YY/4
>   Jan1Weekday = 1 + (((((C / 100) % 4) x 5) + G) % 7)
>6. Find the Weekday for Y M D
>   H = DayOfYearNumber + (Jan1Weekday - 1)
>   Weekday = 1 + ((H -1) % 7)
>7. Find if Y M D falls in YearNumber Y-1, WeekNumber 52 or 53
>   if DayOfYearNumber <= (8-Jan1Weekday) and Jan1Weekday > 4
>      then
>         YearNumber = Y - 1
>         if Jan1Weekday = 5 or (Jan1Weekday = 6 and Y-1 is LeapYear)
>            then
>               WeekNumber = 53
>            else
>               WeekNumber = 52
>      else
>         YearNumber = Y
>8. Find if Y M D falls in YearNumber Y+1, WeekNumber 1
>   if YearNumber = Y
>      then
>         if Y is LeapYear
>            then
>               I = 366
>               else
>               I = 365
>         if (I - DayOfYearNumber) < (4 - Weekday)
>            then
>               YearNumber = Y + 1
>               WeekNumber = 1
>9. Find if Y M D falls in YearNumber Y, WeekNumber 1 through 53
>   if YearNumber = Y
>      then
>         J = DayOfYearNumber + (7 - Weekday) + (Jan1Weekday -1)
>         WeekNumber = J / 7
>         if Jan1Weekday > 4
>               WeekNumber -= 1
>10. Output ISO Week Date:
>   if WeekNumber < 10
>      then
>         WeekNumber = "0" & WeekNumber  (WeekNumber requires 2 digits)
>   YearNumber - WeekNumber - Weekday    (Optional: "W" & WeekNumber)
>