Simplicity 5196 vintage sewing pattern, dated 1972. 

Misses' Bias-Skirt in Two Lengths, Shirt and Top - (Top Designed for Knit Fabrics Only):

The top with back zipper has roll collar and long set-in sleeves. The top-stitched shirt with front button closing has shirt type collar, front band, button trimmed shoulder tabs, long set-in sleeves pleated to buttoned cuffs and optional patch pocket. The long or short bias skirt has side zipper and waistband. The long skirt is ankle length. The short skirt is mini-length. All garments have optional purchased belt. 

Size  12:

Bust  34 inches / 87 cm

Waist 26 1/2 inches / 67 cm

Hip    36 inches / 92 cm

Pattern pieces for skirt are cut and checked complete; cut to short length with extensions included for maxi length. Envelope is torn across top.

More '70s patterns here:

http://allthepreciousthings.com/collections/1970s