My mom taught me a way of thinking about purchases when I was a kid. I think it was part of my Real Life Math homeschool learning. She said that when you buy something, you can divide the price by the number of times you use it to figure out how much it costs per use.

Of course, more expensive items or seasonal items that only get pulled out at certain times of the year take longer to bring the per-use cost down.

In 2014, I climbed Mt. Hood in Oregon with my dad and my sibs. It was in celebration of my dad’s 60th birthday.

It was the most terrifying thing I’ve ever done. Despite it being June, an icy wind was blowing when we started the climb in the middle of the night. The tiny crystals were flying in our faces, and I felt like an ant clinging to the surface of the impossibly huge face of the mountain. Our crampons kept us from slipping off the slick surface of the icy snow, but it felt like we could fly off the slope with next gust of wind.

The fancy hiking boots and ski-grade mittens I’d purchased for the climb kept me warm and dry. When I came back to New York, I didn’t need them anymore. While it was winter up on the mountain, it was spring back home. The boots and mittens went in the storage space where we keep our off-season clothes.

When I went back to Oregon with the Chaplain a couple of years later, I brought the boots and wore them all the time during our visit, on our many hikes. Then they went back in storage again. I already had a pair of winter boots, so I rarely used them. The mittens came out during the occasional snowstorm, for shoveling, but they are too bulky for everyday use.

As this past summer came to a close, the Chaplain and I talked many times about walking through the winter. We wondered if we could make ourselves walk in the cold and dark, in ice, snow, and slush.

The weather got colder, and we grew accustomed to walking in the dark most of the time. Instead of walking 6 nights a week, we walk 3-4, often taking shorter routes to limit our time in the cold. I pulled my hiking boots out at some point and started wearing them on our walks. The mittens made an appearance, too, after a particularly frigid night when my regular gloves didn’t cut it.

I like the cheery red laces of my boots, and the leather palms of the mittens. I like the fact that finally, 5 years after I got them, it’s starting to feel like the per-use cost for both of them is in a range I can live with. The point when I’ve gotten my money’s worth from an item is when I can no longer remember how many times I’ve worn it, and I’m there.

Do you keep track of the per-use cost of anything you buy? Are there any items that cause an immediate stab of guilt when you start to make the calculation? Is not doing a per-use cost analysis for everything a sign of privilege?

Does the idea of walking on a wintery evening make you shiver? Or does it bring you back to the last time you took a dark, winter walk – breathing in the crisp air, watching the snow fall in the quiet magic of a cold night?