[aredington]

There's a growth in both supply and demand, let's call them ds and dd. ds is relatively constant, though every 4 years it halves. dd is stochastic and gets influenced by how many ways there are to use bitcoins as a store of wealth, speculative opinions on its future conversion to dollars, and how many actors will accept bitcoins as a transfer of wealth.

Most of the pressure on dd has directed it to grow, so demand is going up, and it goes up faster over time. ds is a designed feature of the currency, and is designed to shrink quasi-deterministically.

The supply of bitcoins is not growing in proportion to the growth of demand for bitcoins, thus the price goes up. So it's probably most fair to say that the demand is growing significantly faster than the suppply. However, the most recent halving day has significantly altered the differential between ds and dd.