UNICOM Intelligence Reporter - Survey Tabulation performs all calculations using the maximum possible accuracy and only performs rounding immediately before it displays figures in a table. UNICOM Intelligence Reporter - Survey Tabulation uses a standard rounding algorithm when it performs rounding. When rounding a real number to an integer, for example, UNICOM Intelligence Reporter - Survey Tabulation rounds to the nearest integer, except where the decimal places are exactly 5. In these cases, it rounds to the even integer by default. This means that of the two possible rounded values, the one that has an even number as the last significant digit is returned. For example, 15.25 is rounded to 15.2 rather than 15.3. To instead round half values up, set the RoundingOptions property to 1. For more information, see Table properties.

Apparent anomalies when you change the accuracy of cell contents that are real numbers can usually be explained by the fact that UNICOM Intelligence Reporter - Survey Tabulation performs each rounding calculation separately using the maximum possible accuracy. For example, when you display a weighted count of 51.4999999 with one decimal place, it is shown as 51.5. If you choose to display it without decimal places, it becomes 51. At first sight, you might think this is incorrect because 51.5 should be rounded to 52. However, UNICOM Intelligence Reporter - Survey Tabulation performs each rounding calculation separately from the unrounded value, which in this example is 51.4999999, and the figure of 51 is in fact correct.

During the calculation of a base in a weighted table (for example, from counts for use in a percentage calculation), UNICOM Intelligence Reporter - Survey Tabulation uses the maximum possible accuracy of the contributing values. If the base is subsequently displayed in the table, UNICOM Intelligence Reporter - Survey Tabulation rounds it to the same number of decimal places as the counts. This means that sometimes a base displayed in a table is not exactly equal to the sum of the counts displayed in the contributing cells.

For example, the following table shows the values both before and after rounding of the counts for two cells and the base that UNICOM Intelligence Reporter - Survey Tabulation calculates:

When you show row or column percentages in a table, UNICOM Intelligence Reporter - Survey Tabulation can optionally manipulate the percentages to eliminate anomalies such as these. You can do this by selecting Adjust rounding so that percentages add up to 100%. See To set percentage options for more information.

IBM SPSS Statistics calculates table totals from the rounded values shown in the table. In a corresponding IBM SPSS Statistics table containing the same figures, the total is shown as 7.