Metallicity (top panel) and spatial distribution in Galactic coordinates (middle panel) and Cartesian coordinates (bottom panel) for datasets of RR Lyrae (blue squares) and nonvariable giants (orange points). The solid white lines in the top panel depict the approximate footprint of the OGLE survey. In the bottom panel, the black lines indicate the surface density contours (of the analytical potential) for a stellar component rotated by the bar angle (25 degrees). The underlying image in the top panel is the Gaiaall-sky star density map. Image credit: ESA/Gaia/DPAC. Images released under CC BY-SA 3.0 IGO.