What we sing about reflects our hopes and desires, the direction and impetus of our faith. Therefore, looking at the percentage of published hymns containing certain keywords over time can reveal significant trends.
Do North American Christians place more of their hope in this world and less in the next than they did a couple of centuries ago? Perhaps the hymns published in hymnals would help us address this question. Give our new search graphing widget a try and see how commonly published hymns mention "heaven" or "hell" over the years.