This is because the increase in the consumption tax rate is smaller than that of the most recent tax hike and a reduced tax rate will be applied to some items.
In addition, as the consumption tax hike is scheduled to take place in the middle of the fiscal year, there are technical factors; namely, that the front-loaded increase and subsequent decline in demand prior to and after the hike will offset each other during the fiscal year, and a decline in real income could only occur in the second half of the fiscal year.