Regression analysis: selecting TREND or FORECAST formula


I am doing a regression analysis on average price increases from a PPI table, and my goal is to project a 2013 value using the average yearly value from 1985 - 2012. Excel gives me two formulas to do this -- TREND and FORECAST -- and both formulas appear to perform a regression analysis or use a best fit curve to project future values. The formulas, however, give different results.
I researched these formulas on Microsoft's help pages, and it appears TREND is the more complex formula, able to handle multiple columns of data that affect the dependent variable. I do not see any way to differentiate these formulas based on my needs, however, so I'm having trouble selecting the correct one. On a very basic level, I think I want the formula that would give me the answer corresponding to a linear "best fit" line, similar to what you would get if you graphed previous year's data points on an X-Y axis and simply took a ruler to draw a straight line going through the 2013 value. It seems FORECAST is the simpler formula to use, but I would also like to understand whether TREND can be used.
Any advice on this seemingly simple question would be very much appreciated. I have a strong background in Excel and financial modeling, but have not been trained in Statistics. Any reference to related post or other online resource would be appreciated!

Thank you