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We present a long-term overview of the atmospheric phase stability at theAtacama Large Millimeter/submillimeter Array (ALMA) site, using >5 years ofdata, that acts as the successor to the studies summarized two decades ago byEvans et al 2003. Importantly, we explore the atmospheric variations, the`phase RMS', and associated metadata of over 17000 accrued ALMA observationstaken since Cycle 3 (2015) by using the Bandpass calibrator source scans. Weindicate the temporal phase RMS trends for average baseline lengths of 500,1000, 5000, and 10000m, in contrast to the old stability studies that used asingle 300m baseline phase monitor system. At the ALMA site, on the Chajnantorplateau, we report the diurnal variations and monthly changes in the phase RMSon ALMA relevant baselines lengths, measured directly from data, and wereaffirm such trends in atmospheric transmission (via Precipitable Water Vapour- PWV). We confirm that day observations have respectively higher phase RMS andPWV in contrast to night, while the monthly variations show Chilean winter(June - August) providing the best, high-frequency and long-baseline observingconditions - low (stable) phase RMS and low PWV. Yet, not all good phasestability condition occur when the PWV is low. Measurements of the phase RMS asa function of short timescales, 30 to 240s, that tie with typical target sourcescan times, and as a function of baseline length indicate that phase variationsare smaller for short timescales and baselines and larger for longer timescalesand baselines. We illustrate that fast-switching phase-referencing techniques,that allow short target scan times, could work well in reducing the phase RMSto suitable levels specifically for high-frequencies (Band 8, 9 and 10),long-baselines, and the two combined.

Updates to ALMA Site Properties: using the ESO-Allegro Phase RMS database -- ALMA Memo 624