Assistance Please

jan feb mar apr may june july aug sep oct nov dec 12 mth
Bakkies 5 9 56 45 34 13 87 90 54 34 34 54 519
cars 7 8 23 34 76 9 19 23 35 56 38 34
467
trucks 23 56 67 45 76 32 54 23 56 23 54 54 762

I have a excell spreadsheet setup as above and every month i add a new colum
I would like to write a macro that can enable me to display 6 month data and
12 months data alternately or in other words hide and unhide unnecssary
colums

Please help