The Bear Room, page-2327

Here's our answer Tradie, but if ZIP gets back into the ASX200 the shorts might lay out the welcome back mat lol

'Missing' short data may be from shorting that falls below the reporting thresholds (AUD 100,000 or 0.01% of total shares on issue) or simply the fact that the stock in question has zero short interest on the day in question. Our treatment assumes the latter. The proportion of stock-day observations with missing short interest is only 1.76%. Missing observations are concentrated in stocks with very low levels of short interest, with the mean (median) short interest immediately prior to missing observation of 0.2% (0.007%). The results are unchanged if we adopt an alternate treatment of replacing missing observations with the last reported short interest.

The analysis is restricted to the constituents of the S&P/ASX200 Index. As the primary benchmark for the Australian market, the S&P/ASX200 represents the investable universe for many institutional investors.5 This sample choice is compelled by the fact that stocks outside the benchmark index are difficult and expensive to short. Table 1 illustrates that shorting is virtually non-existent outside the 200 largest stocks. As such, low (or no) short-selling activity in nonindex stocks may be more indicative of impediments to shorting than lack of negative sentiment.