Filter library for a moving average

This morning I finished the first class in a Filter library called Moving_average. I'm using it to smooth inputs from an accelerometer for input into a fuzzy logic controller.

However, I searched for forums and saw lots of questions about smoothing data, and moving averages to reduce the noise in a sensor so I wanted to make this library available on the forum for anyone looking to smooth data before they use it in a control loop.

The library allows you to implement a moving_average and specify how many data points you want to smooth over and an optional parameter to set the default value of the historical data_points before you add your first "actual" sensor reading. The constructor signature is:

Moving_average(int length_to_smooth, int default_data = 0);

The code also handles memory carefully to avoid overflows from continuously adding new data points.

I'd like any comments from folks on how to improve the library and hopefully others will find it useful for their own projects.

This isn't the place. Other Software Development is.