A rupee today is worth less than a rupee yesterday. This reality escapes many investors who think they will invest or save more only when they have enough money. With inflation constantly eroding the value of money, the amount that seems substantial today will not have the same value a few years down the line. For example, with inflation of say 7%, today's Rs.5,000 will be worth Rs.4,650 next year, Rs.4,021 in 3 years and Rs.3,479 in 5 years. Meaning, you are saving less with fixed SIPs. That is why growing your monthly SIP amount is more of a requirement to overcome inflation. In our case, this SIP should have grown by at least Rs.500 every year to stay ahead of the inflation loss.
A finer point to note here is that the incremental worth of Rs.500 itself will diminish over the years. Hence, one should look to increase SIPs in blocks of say 3 years like for example, grow your SIP by Rs.500 for the next 3 years and then by Rs.1,000 next 3 years and then Rs,1,500 next and so on considering a base SIP of Rs.5,000, keeping in mind just the inflation.