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Full list of authors: Makhathini, S.; Mooley, K. P.; Brightman, M.; Hotokezaka, K.; Nayana, A. J.; Intema, H. T.; Dobie, D.; Lenc, E.; Perley, D. A.; Fremling, C.; Moldòn, J.; Lazzati, D.; Kaplan, D. L.; Balasubramanian, A.; Brown, I. S.; Carbone, D.; Chandra, P.; Corsi, A.; Camilo, F.; Deller, A.; Frail, D. A.; Murphy, T.; Murphy, E. J.; Nakar, E.; Smirnov, O.; Beswick, R. J.; Fender, R.; Hallinan, G.; Heywood, I.; Kasliwal, M.; Lee, B.; Lu, W.; Rana, J.; Perkins, S.; White, S. V.; Józsa, G. I. G.; Hugo, B. ; Kamphuis, P., We present the full panchromatic afterglow light-curve data of GW170817, including new radio data as well as archival optical and X-ray data, between 0.5 and 940 days post-merger. By compiling all archival data and reprocessing a subset of it, we have evaluated the impact of differences in data processing or flux determination methods used by different groups and attempted to mitigate these differences to provide a more uniform data set. Simple power-law fits to the uniform afterglow light curve indicate a t 0.86±0.04 rise, a t -1.92±0.12 decline, and a peak occurring at 155 ± 4 days. The afterglow is optically thin throughout its evolution, consistent with a single spectral index (-0.584 ± 0.002) across all epochs. This gives a precise and updated estimate of the electron power-law index, p = 2.168 ± 0.004. By studying the diffuse X-ray emission from the host galaxy, we place a conservative upper limit on the hot ionized interstellar medium density, The MeerKAT telescope is operated by the South African Radio Astronomy Observatory, (SARAO), which is a facility of the National Research Foundation (NRF), an agency of the Department of Science and Technology. K.P.M. is a Jansky Fellow of the National Radio Astronomy Observatory. K.P.M. and G.H. acknowledge support from the National Science Foundation Grant AST-1911199. D.D. is supported by an Australian Government Research Training Program Scholarship. T.M. acknowledges the support of the Australian Research Council through grant DP190100561. Parts of this research were conducted by the Australian Research Council Centre of Excellence for Gravitational Wave Discovery (OzGrav), project number CE170100004. We acknowledge support by the GROWTH (Global Relay of Observatories Watching Transients Happen) project funded by the National Science Foundation PIRE (Partnership in International Research and Education) program under grant No. 1545949. D.L. acknowledges support from NASA grants 80NSSC18K1729 (Fermi) and NNX17AK42G (ATP), Chandra grant TM9-20002X, and NSF grant AST-1907955. This research has made use of NASA's Astrophysics Data System Bibliographic Services. C.F. gratefully acknowledges support of his research by the Heising-Simons Foundation. JM acknowledges financial support from the State Agency for Research of the Spanish MCIU through the "Center of Excellence Severo Ochoa" award to the Instituto de Astrofísica de Andalucía (SEV-2017-0709) and from the grant RTI2018-096228-B-C31 (MICIU/FEDER, EU). D.L.K. was supported by NSF grant AST-1816492. P.K. is partially supported by the BMBF project 05A17PC2for D-MeerKAT. A.B. and A.C. acknowledge support from the National Science Foundation via grant #1907975.