As shown in the following table, demand for robotic-assisted surgeries at TechCare Hospital has increased at an irregular rate over the past few years:

Year	1	2	3	4	5	6
Surgeries	25	30	33	41	38	49

The director of medical services predicted 6 years ago that demand in year 1 would be 24 surgeries.

a) Use exponential smoothing with a smoothing constant of =0.4 , to develop forecasts for years 2 through 6. Calculate the Mean Absolute Percentage Error (MAPE) for this case.

b) Use trend-adjusted exponential smoothing to forecast demand for years 2 through 6 with smoothing constants of =0.4 and =0.7 . Assume that the initial trend adjustment is -3. Calculate the MAPE for this case.

c) With MAPE as the criterion, which of the two forecasting methods is best?