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Based on high-resolution spectra obtained during gravitational microlensingevents we present a detailed elemental abundance analysis of 32 dwarf andsubgiant stars in the Galactic bulge. [ABRIDGED], we now have 58 microlensedbulge dwarfs and subgiants that have been homogeneously analysed. The maincharacteristics of the sample and the findings that can be drawn are: (i) Themetallicity distribution (MDF) is wide and spans all metallicities between[Fe/H]=-1.9 to +0.6; (ii) The dip in the MDF around solar metallicity that wasapparent in our previous analysis of a smaller sample (26 microlensed stars) isno longer evident; instead it has a complex structure and indications ofmultiple components are starting to emerge. [ABRIDGED]; (iii) The stars with[Fe/H]<-0.1 are old with ages between 10 and 12 Gyr; (iv) The metal-rich starswith [Fe/H]>-0.1 show a wide variety of ages, ranging from 2 to 12 Gyr with adistribution that has a dominant peak around 4-5 Gyr and a tail towards higherages; (v) There are indications in the [alpha/Fe] - [Fe/H] that the "knee"occurs around [Fe/H] = -0.3 to -0.2, which is a slightly higher metallicity ascompared to the "knee" for the local thick disk. This suggests that thechemical enrichment of the metal-poor bulge has been somewhat faster than whatis observed for the local thick disk. The results from the microlensed bulgedwarf stars in combination with other findings in the literature, in particularthe evidence that the bulge has cylindrical rotation, indicate that the MilkyWay could be an almost pure disk galaxy. The bulge would then just be aconglomerate of the other Galactic stellar populations (thin disk, thick disk,halo, and ...?), residing together in the central parts of the Galaxy,influenced by the Galactic bar.

Chemical evolution of the Galactic bulge as traced by microlensed dwarf and subgiant stars. V. Evidence for a wide age distribution and a complex MDF