I like the idea of some kind of database but there are a lot of variables to consider. Even the size of glove you wear makes a difference. If the gloves are too tight they will be colder, larger roomier gloves trap more warm air and allow more movement of the fingers and better circulation.

How well the rest of you is dressed will also affect how warm your hands stay. If you head and core are chilled, the body's defense is to shunt blood from the extremities to protect the vital organs including the brain. There is an old saying among outdoorsmen, "If your feet are cold the first thing you need is a better hat." It's true that if your head and torso are properly insulated you can probably tolerate an additional -10 degrees F with the same boots and gloves, compared to if you are chilled all over.

Another thing that is going to affect your results is that different people have different cold tolerances. In my 20s I wore lightly insulated gloves during all kinds of winter activity and rarely got cold fingers. Now nearing 50, my hands get cold much more easily and I've had to resort to thicker gloves, layered gloves, or heavy mittens. My sister has always had cold hands and needed twice the glove I did even when we were in high school.

That said, the weather today was around 15F clear with just a very light breeze. I did 20 miles on the highway at an average speed of 15 mph on a trail bike which is also my winter bike. My gloves were Ice Armor medium duty gloves over a pair of wool liners. I was good for the first hour but the last six miles or so my fingers got cold enough to sting despite taking my hands off the bar alternately to flex and shake them every few minutes.