The sky promised a good sunset, so we set out for Lake Champlain after supper. As luck would have it, clouds rolled in during the short drive, depriving us of the sunset we anticipated. I still thought this was interesting. Although the temperatures have gotten a lot warmer (it was thirty-eight) the lake is what economists call a lagging indicator: it tells us what happened sometime in the recent past. It typically does not freeze until end of January or early February. Now that it is frozen, it will stay that way until mid-April.