I suspected it would also depend on how it is cooked, so looked up raw and cooked squash & pumpkin on nutritiondata.com. Pumpkin always seemed sweeter than acorn squash to me, but it is less carby. I used weights since they are more accurate:

100g Squash, acorn, raw: 10g carbs - 1g fiber = 9g net
100g Squash, acorn, baked: 15g carbs - 4g fiber = 11g net
100g Squash, acorn, boiled: 22g carbs - 6g fiber = 16g net

100g Pumpkin, raw: 6g carbs - 0g fiber = 6g net
100g Pumpkin, canned: 8g carbs - 3g fiber = 5g net
Pumpkin, boiled, drained: 5g carbs - 1g fiber = 4g net

I don't eat them raw, but sometimes measure them raw and then steam or nuke, rather than bake or boil, then mash. 100g is a decent sized serving, 3.5 oz.