That is a visual glitch. I'm guessing that you're Modern Era or higher. At that stage, the Dresden produces 2x unrefined goods instead of 1x current goods. Since you are at level 12 (I'm assuming you're just looking at where it has current level and next level), you are getting 38 goods instead of the 19 you would be getting if you were below Modern Era. However, the stats for the next level don't reflect this, they simply state the regular pre-Modern output, which would be 20 goods. When you actually level it up, you will get 40 goods, not 20. And the display will again be misleading for level 14.