Consumer sentiment in Japan improved in April from the previous month, with a nationwide consumer confidence index climbing to the highest level in more than seven years, the government said Wednesday.

The Cabinet Office said the unadjusted consumer confidence index for nationwide households, excluding single-person households, rose 2.7 points from March to 45.4, marking the highest reading since September 1996.

The index is calculated by assigning points on the basis of whether consumers believe their sentiment in four categories -- employment, overall livelihood, income growth and inclination to purchase durable goods -- in the coming six months will "improve," "improve somewhat," "remain unchanged," "deteriorate somewhat" or "deteriorate."