For long forms, those with many rows, some extra visual cue should be provided to help a user scan a row accurately across columns.
Additional Information:
Visual aids for scanning rows are probably needed more when a user is reviewing and changing displayed data than for initial data entry. Such aids should be provided consistently, however, so that display formats for both data entry and review will be compatible. For example, a blank line might be inserted after every fifth row, or dots might be placed between columns in every fifth row. As an alternative, a displayed ruler that a user can move from one row to another may be used.