Short Interest

Coverage

7 Nov 2012 – 8 Sep 2026

Frequency

Daily

Files

3

NEFIN computes three daily statistics for the Brazilian stock loan market: the short interest (shares on loan over shares outstanding), the days-to-cover (shares on loan over the average daily number of shares traded in the previous 30 sessions) and the loan fee. Each is averaged across eligible stocks, weighted by the value of open loan positions.

Days-to-cover is in days since the October 2026 update. Earlier versions of this file used a different volume measure in the denominator, which put the series around 0.4; the current series follows the methodology and sits around 7 days. The whole history was recomputed, so re-download the file rather than appending to an old copy. Short interest is in per mille of shares outstanding (32 = 3.2%), and the loan fee in percent per year; both are now computed over eligible stocks only, as in the methodology. A weekly version of the loan fee, as a fraction, is on the Loan Fees page.

# Python
import pandas as pd
df = pd.read_csv("https://nefin.com.br/nefindata/short-interest/average_short_interest.csv")

# R
df <- readr::read_csv("https://nefin.com.br/nefindata/short-interest/average_short_interest.csv")

NEFIN (2026). Short Interest.
Center for Research in Financial Economics, University of São Paulo.
https://nefin.com.br/data/short-interest/