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We present a new measurement of the Ly$\alpha$ luminosity function atredshift $z=6.9$, finding moderate evolution from $z=5.7$ that is consistentwith a fully or largely ionized $z\sim7$ intergalactic medium. Our result isbased on four fields of the LAGER (Lyman Alpha Galaxies in the Epoch ofReionization) project. Our survey volume of $6.1\times10^{6}$ Mpc$^{3}$ isdouble that of the next largest $z\sim 7$ survey. We combine two new LAGERfields (WIDE12 and GAMA15A) with two previously reported LAGER fields (COSMOSand CDFS). In the new fields, we identify $N=95$ new $z=6.9$ Ly$\alpha$emitters (LAEs); characterize our survey's completeness and reliability; andcompute Ly$\alpha$ luminosity functions. The best-fit Schechter luminosityfunction parameters for all four LAGER fields are in good general agreement.Two fields (COSMOS and WIDE12) show evidence for a bright-end excess above theSchechter function fit. We find that the Ly$\alpha$ luminosity density declinesat the same rate as the UV continuum LF from $z=5.7$ to $z=6.9$. This isconsistent with an intergalactic medium that was fully ionized as early asredshift $z\sim 7$, or with a volume-averaged neutral hydrogen fraction of$x_{HI} < 0.33$ at $1\sigma$.

LAGER Ly$\alpha$ Luminosity Function at $z\sim7$, Implications for Reionization