In any municipality electing this subdivision, or any district wholly within a town electing this subdivision, the total amount appropriated at any annual meeting shall not exceed by more than 10 percent the total amount recommended by the budget committee for such meeting. In official ballot referendum municipalities, the recommendation of the budget committee made for the first session of the meeting shall be used for determining the 10 percent limitation. These totals shall include appropriations contained in special warrant articles. Money may be raised and appropriated for purposes included in the budget or in the warrant and not recommended by the budget committee, but not to an amount which would increase the total appropriations by more than the 10 percent allowed under this paragraph. The 10 percent increase allowable under this paragraph shall be computed on the total amount recommended by the budget committee less that part of any appropriation item which constitutes fixed charges. Fixed charges shall include appropriations for:
I. Bonds, and all interest and principal payments thereon.
II. Notes, except tax anticipation notes, and all interest and principal payments thereon.
III. Mandatory assessments imposed on towns by the county, state or federal governments.