Most posts are giving mpg for a 5 speed. An automatic will get lower mpg in city driving than a 5 speed. My 02 P5 automatic usually gets 22-26 mpg for city driving, I live in a small city. It did about the same when I purchased it new. The only time I have gone over 400 miles on a tank was on highway trips.
On extended trips (NC-CO and WA) I get 30-34 depending on speed and altitude. 75 mph hurts fuel mpg and so does ethanol fuel. Higher altitudes will normally help mpg.
Before doing anything I would take the car on a highway trip long enough to use a tank of fuel. If you are getting 29-32 mpg it's probably normal. The automatic car turns around 3k rpm at around 67-68 mph. It's shifting pattern is programed for performance rather than high mpg. In city driving where speeds are less than 35-40 the transmission torque converter isn't locked up and that hurts mpg. Frequent changes in speed also prevents the torque converter from locking up.
In short, there is usually a penalty in mpg when moving from a stick shift to an automatic.
Clifton
This is exactly the situation we are in. The wife uses the car primarily for really short daily drives to work with several traffic lights and probably never sees 40 mph. We are switching cars this week because my job involves long drives at highway speeds. This should give us a better read on what the car is doing. We both really like the car. Finding a well cared for, low mileage at a good price example was lucky.
Thanks all for your input and advice.