Social Security Number typing and saving...

Hi, and many thanks for your help, we appreciate it

We are not the best coding so we will try our best.

We are a attorney at law office and we register all info about our customers, including the Social Securty Number (SS#), as probably you all know, the formatted way to type it is "###-##-####)  but we created a text field that has no format, and our people just type in the fastest way they can, so we got some registry typed as (#########) or (#### - ####) and that is not the correct way to keep a Social security number.

So, the question: is there a way to created a autoformat field like the "date" field, that, when someone type the number it just auto correct to (mm-dd-yyyy), no matter what you type in, it autocorrect himself? - I been trying and reading other post but can not figure out. 

We would preffer a autocorrect field, that corrects himself on the form, not creating another field that with a formula "totext" converts the exiting field on form and then converts it to formmated text in another field to display. (mainly cause no one will know how it will be saved until you already save the registry)

Many thanks. (We do not even know if this is possible, we are open to other smart solutions)