Calculate the Consumer Price Index (CPI) for the years 2011 to 2014, using 2010 as the base year with a price of KShs 90. The prices for subsequent years are: 2011 (KShs 85), 2012 (KShs 90), 2013 (KSh

The formula for CPI is:

The base year is 2010, and its price is KShs 90.

• For 2010: Price = KShs 90

  $$\text{CPI}_{2010} = \frac{90}{90} \times 100 = 100$$

• For 2011: Price = KShs 85

  $$\text{CPI}_{2011} = \frac{85}{90} \times 100 \approx 94.44$$

• For 2012: Price = KShs 90

  $$\text{CPI}_{2012} = \frac{90}{90} \times 100 = 100$$

• For 2013: Price = KShs 100

  $$\text{CPI}_{2013} = \frac{100}{90} \times 100 \approx 111.11$$

• For 2014: Price = KShs 120

  $$\text{CPI}_{2014} = \frac{120}{90} \times 100 \approx 133.33$$

The calculated consumer price indices are:

• 2011: 94.44
• 2012: 100
• 2013: 111.11
• 2014: 133.33