Ash/Amuchastegui - June 69  double precision function A1WWV
7/17/98 updated for 1999 Jan 1 quantum jump, plus a guess at the next
1/10/01 re-revised guess of the next leap second
1/15/03 removed guess of the next leap second
7/18/05 updated for 2006 Jan 1 leap second (at last)
7/04/08 updated for 2009 Jan 1 leap second
1/05/12 updated for 2012 Jul 1 leap second
1/05/15 updated for 2015 Jul 1 leap second
7/06/16 updated for 2017 Jan 1 leap second

Calculate A.1-WWV time from 1956.
Linear interpolation from final bulletins at ten day intervals
from January 1956 to January 1966.
Linear formula used thereafter.
$$$$ routine to be revised as history progresses

frequency offset of WWV from A.1 in units of 10**-10
1956 Jan 07 to 1957 Aug 19 frequency offset varied between -36 to -98
1957 Aug 29 to 1958 Dec 22 frequency offset varied between -83 to -127
1959 Jan 01 to 1959 Dec 31 frequency offset varied between -92 to -112
1960 to 1961  frequency offset was kept near -150
1962 to 1963  frequency offset was kept near -130 (change in slope
1962 Jan 1 ignored between tabular points)
1964 to 1965  frequency offset was kept near -150 (change in slope
1964 Jan 1 ignored between tabular points)
1966 to 1971  frequency offset was kept at   -300
1972 to ----  frequency offset was kept at   0
linear formulae used from from 1966 Jan 1 to
1972 Jan 1
step function used after 1972 Jan 1

points at which discontinuities occurred
amount   between   Julian
instant of jump   of jump  tabular   day
year month day hr  (sec)    points    number
1956 Jan    4  19  0.061              2435477   not in range of table
March  7  19 -0.020     7   8    2435540
March 28  19 -0.020     9  10    2435561
July  26  19  0.020    21  22    2435681
Aug   22  19  0.020    23  24    2435708
Sept  19  19  0.020    26  27    2435736
Oct   31  19  0.020    30  31    2435778
Nov   14  19  0.020    32  33    2435792
1957 Jan   23  19  0.020    39  40    2435862
Mar   13  19  0.020    44  45    2435911
May   01  19  0.020    49  50    2435960
June  05  19  0.020    52  53    2435995
June  19  19  0.020    53  54    2436009
July  03  19  0.020    55  56    2436023
July  17  19  0.020    56  57    2436037
Aug   14  19  0.020    59  60    2436065
Oct   16  19  0.020    65  66    2436128
Nov   06  19  0.020    67  68    2436149
Dec   11  19  0.020    71  72    2436184
1958 Jan   15  19  0.020    74  75    2436219
Feb   05  19  0.020    77  78    2436240
Feb   19  19  0.020    78  79    2436254
April 09  19  0.020    83  84    2436303
June  11  19  0.020    89  90    2436366
July  02  19  0.020    91  92    2436387
July  16  19  0.020    93  94    2436401
Oct   22  19  0.020   102 103    2436499
Nov   26  19  0.020   106 107    2436534
Dec   24  19  0.020   109 110    2436562
1959 Jan   28  19  0.020   112 113    2436597
Feb   25  19  0.020   115 116    2436625
Aug   05  19  0.020   131 132    2436786
Aug   26  19  0.020   133 134    2436807
Sept  30  19  0.020   137 138    2436842
Nov   04  19  0.020   140 141    2436877
Nov   18  19  0.020   142 143    2436891
Dec   16  19  0.020   144 145    2436919
1961 Jan   01  00  0.005   183 184    2437301
Aug   01  00 -0.050   204 205    2437513
1963 Nov   01  00  0.100   286 287    2438335
1964 April 01  00  0.100   301 302    2438487
Sept  01  00  0.100   316 317    2438640
Oct   01  00  0.001   319 320    2438670
1965 Jan   01  00  0.100   329 330    2438762
March 01  00  0.100   335 336    2438821
July  01  00  0.100   347 348    2438943
Sept  01  00  0.100   353 354    2439005
1966 Dec   01  00 -0.0007             2439461   linear formulae
1968 Feb   01  00 -0.100              2439888
1972 Jan   01  00  0.1076             2441318   step function
Jul   01  00  1.0                2441500
1973 Jan   01  00  1.0                2441684
1974 Jan   01  00  1.0                2442049
1975 Jan   01  00  1.0                2442414
1976 Jan   01  00  1.0                2442779
1977 Jan   01  00  1.0                2443145
1978 Jan   01  00  1.0                2443510
1979 Jan   01  00  1.0                2443875
1980 Jan   01  00  1.0                2444240
1981 Jul   01  00  1.0                2444787
1982 Jul   01  00  1.0                2445152
1983 Jul   01  00  1.0                2445517
1985 Jul   01  00  1.0                2446248
1988 Jan   01  00  1.0                2447162
1990 Jan   01  00  1.0                2447893
1991 Jan   01  00  1.0                2448258
1992 Jul   01  00  1.0                2448805
1993 Jul   01  00  1.0                2449170
1994 Jul   01  00  1.0                2449535
1996 Jan   01  00  1.0                2450084
1997 Jul   01  00  1.0                2450631
1999 Jan   01  00  1.0                2451180
2006 Jan   01  00  1.0                2453737
2009 Jan   01  00  1.0                2454833
2012 Jul   01  00  1.0                2456110
2015 Jul   01  00  1.0                2457205
2017 Jan   01  00  1.0                2457755
$$$$ above comment table to be extended as routine is revised