We derive the statistical properties of neutral gas at redshifts 0.11 < z < 1.65 from UV measurements of quasar Ly \alpha absorption lines corresponding to 369 Mg ii systems with W ^ { \lambda 2796 } _ { 0 } \geq 0.3 Å .
In addition to the 41 damped Lyman alpha ( DLA ) systems presented in Rao et al .
( 2006 ) , the current DLA sample includes 29 newly discovered DLAs .
Of these , 26 were found in our Hubble Space Telescope ( HST ) Advanced Camera for Surveys prism survey for DLAs ( Turnshek et al .
2015 ) and three were found in a GALaxy Evolution Explorer ( GALEX ) archival search .
In addition , an HST Cosmic Origins Spectrograph Cycle 19 survey yielded no DLAs that could be used for this study .
Formally , this DLA sample includes 70 systems with N _ { HI } \geq 2 \times 10 ^ { 20 } atoms cm ^ { -2 } .
We find that the incidence of DLAs , or the product of their gas cross section and their comoving number density , can be described by n _ { DLA } ( z ) = ( 0.027 \pm 0.007 ) ( 1 + z ) ^ { ( 1.682 \pm 0.200 ) } over the redshift range 0 < z < 5 .
The cosmic mass density of neutral gas can be described by \Omega _ { DLA } ( z ) = ( 4.77 \pm 1.60 ) \times 10 ^ { -4 } ( 1 + z ) ^ { ( 0.64 \pm 0.27 ) } .
The low-redshift column density distribution function is well-fitted by a power law of the form f ( N ) \sim N ^ { \beta } with \beta = -1.46 \pm 0.20 .
It is consistent with the high-redshift as well as z = 0 estimates at the high column density end but , lies between them at the low column density end .
We discuss possible N _ { HI } and metallicity bias in Mg ii -selected DLA samples and show that such biases do not exist in the current data at z < 1.65 .
Thus , at least at z < 1.65 , DLAs found through Mg ii selection statistically represent the true population of DLAs .
However , we caution that studies of DLA metallicities should take into the account the relative incidence of DLAs with respect to W _ { 0 } ^ { \lambda 2796 } ( or gas velocity spread ) in order to correctly measure the mean neutral-gas cosmic metallicity of the universe .