Chunky knitting bobble (less) hat

I've used the following...
Chunky wool, size 7mm needles

Body of hat
Cast on 80 stitches, knit 30 rows in garter [plain] stitch

decrease for top of head as follows;
1st row decrease * K14, K2tog * repeat ** 5 times [75sts]
2nd row decrease * K2tog, K13 * repeat ** 5 times [70sts]
3rd row decrease * K12, K2tog * repeat ** 5 times [65sts]
4th row decrease * K2tog, K11 * repeat ** 5 times [60sts]
5th row decrease * K10, K2tog * repeat ** 5 times [55sts]
6th row decrease * K2tog, K9 * repeat ** 5 times [50sts]
7th row decrease * K8, K2tog * repeat ** 5 times [45sts]
8th row decrease * K2tog, K7 * repeat ** 5 times [40sts]
9th row decrease * K6, K2tog * repeat ** 5 times [35sts]
10th row decrease * K2tog, K5* repeat ** 5 times [30sts]
11th row decrease * K4, K2tog * repeat ** 5 times [25sts]
12th row decrease * K2tog, K3 * repeat ** 5 times [20sts]
13th row decrease * K2, K2tog * repeat ** 5 times [15sts]
14th row decrease * K2tog, K13 * repeat ** 5 times [10sts]
Carefully cut wool, leaving a 40 cm ‘tail’ and thread this with large needle
Thread the wool through the 10 stitches, and slide them off the needle.
Gather 10 stitches up tight, and sew the top of the hat together.
Now using the remainder of the tail, carefully sew down the side seam,
finishing at the bottom edge of the hat. Fasten wool off firmly and carefully.
Cut off remaining tail.
Wear hat!

NB if you have no chunky, use 2 strands double knit