Silver's recent rally has been pretty crazy. I looked back at the data from the past few months and just realized—at the start of the year, it was only $116 per ounce, and now I'm wondering how high it can go. Thinking back, silver has gained a huge chunk since the beginning of the year, far surpassing gold's gains, and the gold-silver ratio has dropped to its lowest since 2011.

Major investment banks have some interesting views. Citibank believes silver is currently being used as a hedge against macro risks, but it has more flexibility than gold, which is why it's rising so aggressively. Deutsche Bank and Bank of America are calculating a number—if the gold-silver ratio returns to its 2011 levels, silver could theoretically reach over $150, and in extreme cases, even approach $300. The logic behind this is that the gold-silver ratio will eventually revert to its historical average, but in the short term, silver still has room for growth.

However, caution is advised as CME has recently adjusted the margin requirements for silver futures frequently, which is a move to cool off speculative enthusiasm. Plus, events like the Spring Festival tend to be good opportunities for profit-taking. Goldman Sachs also warns that silver's two-way volatility could be very extreme. So, regarding silver's future trend, the short-term outlook is bullish but with potential for pullbacks. In the long run, it still depends on where the gold-silver ratio ultimately settles.