Three years ago, I put the first Fortune India The Next 500 list together, I had anticipated some churn. I knew some companies would outgrow The Next 500 and move into the Fortune India 500. Of course, I also expected some to fall off both lists, given the overall economy and other factors. But I must confess that this year’s list surprised me by the sheer magnitude of change: 141 companies have disappeared from this list, and only 20 moved into the Fortune India 500. Which means 121 companies have fallen by the wayside.

While some volatility is to be expected when putting together a list such as this, the swings this year seem more dramatic. It’s tempting to lay this at the door of macroeconomics alone (think demonetisation or the dither companies are in because of GST), but that would be unfair. Because the biggest factor impacting the list this year is the availability of verifiable financials; the other is accounting practices that companies follow. Last year, for instance, we had not taken companies such as Ferrero India, Alcatel-Lucent, Perfetti Van Melle India, and Adobe India into consideration. Being foreign-owned, private, and unlisted, the Registrar of Companies gives them more time to submit financial data, and much of this data became available only from this year.

Then, 15 companies in the Fortune India 500 did not grow revenue in line with their peers; those companies fell off the 500, but found a home in The Next 500. What does all this mean to the list? It means that, as always, it relies purely on available data. Which, in turn, means that 28 companies that were on the list last year and which reported increased revenue fell off this year because there were bigger companies in the pool.

Of course, several companies have been removed simply because their numbers fell. But in the interest of fairness, I must point out that not all companies that have fallen off the list have have performed badly; a combination of timing and policy has led to this situation.

Unfortunately, what this bias towards scrupulously fair number-crunching means is that the moves of companies up and down the list don’t really mean a lot. For instance, Gujarat Mineral Development Corporation ranked 6 last year, but has fallen to 122 this year despite doing everything right.

Of course, there are the usual success stories as well. Debutant Sunteck Realty comes in at 412 thanks to a 150% growth in revenue between FY15 and FY16. Others have fallen simply because they have not performed well; last year’s No. 1, Dynamatic Technologies, for instance, drops to 59 this year with a 10.7% fall in revenue.

Dynamatic’s fall is somewhat less dramatic than that of the last company on the list this year, NRB Bearings, which has plunged 73 places. That’s a steep fall for a mere 0.92% drop in revenue. (For those who like to make sense of ranks and numbers, there are 23 new companies between 427—where NRB was last year—and 500, where it is today.)

There’s been equally dramatic movement on the top of the list; Parag Milk Foods zooms from 67 last year to No. 1 on the back of 16.46% growth in revenue.

In the face of such almost illogical moves, it pays to remember the core function of this list: to identify India’s largest midsize companies, and not to track the fastest growing companies or to reward or punish performance.

That said, these movements are strange enough to document and comment upon.

The rest of the list is rather more conventional. As is generally the case, private companies account for the bulk of the list—420 this year. That’s 84% of the list, which accounts for 83.5% of the total The Next 500 revenue. As already mentioned, this year saw a steep rise in the number of foreign-owned companies, from 35 last year to 53.

Continuing the trend of the past years, the manufacturing sector dominates, accounting for 372 of the 500 companies. That translates into a 74.5% revenue share. That’s less than the 83% revenue share last year. Correspondingly, the services sector, with 93 companies, accounts for 18.8% of total revenue.

In terms of revenue clusters, there were 62 companies with revenues in excess of Rs 1,501 crore. The Rs 1,001 crore to Rs 1,250 crore cluster, which had 112 companies compared to 104 last year, saw revenue growth slow to 4.9% compared to 22.7% last year.

Shareholders of the Next 500 companies had reason to cheer, as equity dividend grew 15.6%, compared to a paltry 0.85% last year. But only 283 companies paid dividends between Rs 0.14 crore to Rs 1,157.8 crore (paid by DSP Merrill Lynch, ranked 107). Private companies with 69.7% share of dividend saw 20.8% growth, while government companies with 14.2% share saw 38.3% increase compared to 0.62% decrease last year. In contrast, foreign-owned companies’ annual growth of dividend was 6.6% while they had 16.1% share of the total dividend pie.

What I conclude from all this is that while the constituents of the list can, and do, change dramatically, the overall performance continues to be largely along predictable lines.

Follow us on Facebook, Twitter and YouTube to never miss an update from Fortune India.