Compact midsized are vehicles that will comfortably seat four. A fifth person would have to squeeze into the back seat between two others. For most of us this can be a problem, unless it is kids in the back seat. However, compact and midsized vehicles spew fewer emissions than those of the days before the 1970s. Still on average according to the EPA a typical passenger car gives off 4.6 metric tons of carbon dioxide per year. However, you can offset those emissions and carbon footprint by purchasing carbon credits.