The only reliable and legitimate organization for assigning an Impact Factor to a journal is the Institute for Scientific Information (ISI) of Thomson Reuters. IJDS has not yet applied for inclusion in Thomson Reuters database, however an unofficial calculation based on ISI method indicates an Impact Factor of 0.046 for 2015.
Cites in 2015 to articles published by IJDS in 2013 and 2014 (from ISI database) = 16
Number of articles published by IJDS in 2013 and 2014 = 342
Calculation of Impact Factor for 2015: 16 / 342 = 0.046
UPDATE (2021):
IJDS has not applied for inclusion in Thomson Reuters database, however an unofficial calculation based on ISI method indicates an Impact Factor of 0.076 for 2020.
Cites in 2020 to articles published by IJDS in 2018 and 2019 (from ISI database) = 20
Number of articles published by IJDS in 2013 and 2014 = 260
Calculation of Impact Factor for 2020: 20 / 260 = 0.076