Chicago Cubs Countdown Buttons

I picked these up in a bag with about 50 pin back buttons at a yard sale about a year ago. There were a lot of area school and business buttons showing and these were more in the middle, I didn't see them till I went thru the bag.
I'm not sure the year these were used as there is no makers mark or date on them, also in a little rough shape. We are only a couple hours from chicago and have been to many games since the early 70's and I feel they are from that time frame. A lot of the other buttons were from the late 60's to around 1980.
I just thought I would post them and hope you enjoy, GO CUBS.