My company did a map like this. The highest percentages in 2015-2016 are HI to CA, WY to CO, ND to MN, DE to PA, NH to MA, NM to TX, KS to MO, OR to WA. A map w

My company did a map like this. The highest percentages in 2015-2016 are HI to CA, WY to CO, ND to MN, DE to PA, NH to MA, NM to TX, KS to MO, OR to WA. A map without neighboring states is more interesting.