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tokens: kinematics study of Clarkson et al. ( 2008 ). Awiphan et al. ( 2016 ) presented a more recent version of the model (variant BGM1307) and compared it with a large ensemble of 470 events from the MOA-2 survey (Sumi et al. 2013 ). Awiphan et al. ( 2016 ) concluded that there was a reasonable level of agreement once allowance was made for brown dwarfs that are missing from the BGM. However, the model appeared to underpredict the observed rate from the Galactic bulge significantly. Sumi Penny ( 2016 ) subsequently showed that at least part of the cause of this discrepancy was undercounting of source stars within the MOA-2 analysis and correcting for this resulted in much better agreement with the model. After investigation of a number of different BGM variants, we have decided to use BGM1307 as the basis for MaBμlS-2. The BGM separates the Galaxy into four components; the thin disc, thick disc, bar and halo, each with their own stellar initial mass functions (IMFs), star formation rates (SFRs), kinematics and ages. Interstellar extinction is included for UBVRIJHK photometric bands using a 3D extinction model from Marshall et al. ( 2006 ). The solar position relative to the Galactic Centre and plane in the BGM is taken to be R 0 = 8 kpc and z 0 = 15 pc, respectively. The following description of the Galactic components quotes lower limits on their respective stellar mass functions, but an upper limit is not included. While interesting lens candidates such as intermediate-mass black holes and other compact objects are represented in the high-mass regime, the BGM does not include them. Due to the steepness of the mass functions at high mass, these objects also do not contribute significantly to the overall microlensing parameters outlined in Section 3.1 . 2.1 The thin disc The thin-disc component is subdivided into seven age groups, each with their own luminosity and effective temperature distributions. The mass density is modelled by the difference of two exponentials in cylindrical polar coordinates (r, z) ; one representing the body of the disc with scalelength R d = 2170 pc and the other representing a central hole with scalelength R h = 1330 pc (Robin et al. 2012b ). It is given by where ρ 0 is the component normalization density, and ε is the axial ratio of the ellipsoid. The SFR is taken to be constant across the whole disc. The IMF is given by a broken power law, which is the same across all age groups : Each age group of the thin disc has its own velocity dispersion, to mimic the secular evolution, and follows the relation from Gomez et al. ( 1997 ); these average to km s −1 , with a maximum of km s −1 for the oldest component. The rotational velocity of the local standard of rest (LSR) is 240 km s −1 , with the rotation curve taken from Caldwell Ostriker ( 1981 ). The LSR is defined as the mean velocity of material in the solar neighbourhood, centred on the Sun within 100 pc. The peculiar motion of the Sun relative to the LSR is assumed to