I think "normal" is the following:

Males: 1% per week from the difference between current weight to the 15% target of body fat.

Women: 1% per week from the difference between current weight to the 22% target of body fat.

Slow would be less that 0.5%

The above percentage of fat, are the ones your body expects. Once you reach them, it takes more than dieting to bypass them.

Common misconception for slow is calulating the 1% based on target weight. Or, basing the 1% on current weight, rather than the difference.

Wa'il