Weight Watchers
From Jon's Wiki
Points Formula in SI units:
p = E / 300 kJ + ms / 4 g
Where p is the (dimensionless) points value, E is the overall energy content and ms is the saturated fat content. In practice p is rounded to the nearest ½ point.
Since food labels in New Zealand specify energy content in kilojoules and saturated fat in grams, we can eliminate the units and simplify:
p = E / 300 + ms / 4
For instance 25 g of chocolate is 593 kJ and 5.8 g saturated fat, which is 3½ points.