CIRCULAR T 398 ISSN 1143-1393
2021 MARCH 08, 14h UTC
BUREAU INTERNATIONAL DES POIDS ET MESURES
THE INTERGOVERNMENTAL ORGANIZATION ESTABLISHED BY THE METRE CONVENTION
PAVILLON DE BRETEUIL F-92312 SEVRES CEDEX TEL. +33 1 45 07 70 70 tai@bipm.org

The contents of the sections of BIPM Circular T are fully described in the document " Explanatory supplement to BIPM Circular T "
available at https://webtai.bipm.org/ftp/pub/tai/other-products/notes/explanatory_supplement_v0.4.pdf

1 - Difference between UTC and its local realizations UTC(k) and corresponding uncertainties. From 2017 January 1, 0h UTC, TAI-UTC = 37 s.
Date 2021 0h UTC JAN 30 FEB 4 FEB 9 FEB 14 FEB 19 FEB 24 Uncertainty/ns Notes
MJD 59244 59249 59254 59259 59264 59269 uA uB u
Laboratory k [UTC-UTC(k)]/ns
AOS (Borowiec) -0.4 -0.2 -0.6 -1.0 -0.5 -0.3 0.3 2.9 2.9
APL (Laurel) -0.8 -0.3 -0.8 -0.6 -0.2 0.1 0.3 19.6 19.6
AUS (Sydney) -450.0 -449.1 -442.6 -458.9 -470.1 -473.3 0.3 11.2 11.2
BEV (Wien) -21.2 -21.5 -31.0 -28.1 -39.8 -44.0 0.3 3.3 3.3
BFKH (Budapest) 2008.0 2041.6 2070.7 2099.2 2121.3 2145.2 1.5 20.0 20.1
BIM (Sofiya) 14178.6 14194.3 14235.7 14276.3 14278.8 14320.7 0.7 7.1 7.2
BIRM (Beijing) -0.1 -3.0 -6.4 -9.4 -10.5 -10.9 0.7 2.8 2.9
BOM (Skopje) -4267.1 -4296.6 -4317.0 -4315.1 -4331.8 -4336.6 5.0 7.5 9.0
BY (Minsk) 1.5 2.3 2.8 3.1 3.1 3.3 1.5 12.2 12.3
CAO (Cagliari) -25237.2 -25341.8 -25448.1 -25557.7 -25668.4 -25770.5 1.5 20.0 20.1
CH (Bern-Wabern) 12.5 7.4 3.1 -0.4 -2.9 -2.1 0.3 2.5 2.5
CNES (Toulouse) 4.3 3.4 2.8 1.6 2.1 2.2 0.3 2.9 2.9
CNM (Queretaro) 1.1 -3.2 2.7 2.6 0.4 -3.7 4.0 11.2 11.9
CNMP (Panama) 9.7 8.7 -4.1 -6.5 -13.7 -6.9 0.7 7.3 7.4
DFNT (Tunis) 2236.3 2476.7 2700.5 2938.3 3180.3 3417.0 1.5 20.0 20.1
DLR (Oberpfaffenhofen) - - - - - -
DMDM (Belgrade) -59.0 -51.7 -44.4 -39.7 -36.5 -28.4 0.3 3.3 3.3
DTAG (Frankfurt/M) -18.0 -21.9 -20.5 -21.3 -26.6 -16.9 0.3 2.8 2.8
EIM (Thessaloniki) 2.3 1.1 3.7 8.9 4.0 15.0 4.0 11.2 11.9
ESTC (Noordwijk) -0.3 0.5 0.1 0.1 0.7 0.1 0.3 2.8 2.8
HKO (Hong Kong) 100.4 103.6 97.8 106.6 104.8 96.4 0.5 3.0 3.0
ICE (San Jose) 20.6 32.0 43.5 63.5 65.0 62.4 2.5 20.0 20.2
IDN (Serpong-Tangerang) 2559.7 72.3 102.2 108.4 121.3 134.1 0.3 2.8 2.8 (1)
IFAG (Wettzell) -792.3 -797.4 -798.6 -796.7 -803.8 -805.0 0.3 3.2 3.2
IGNA (Buenos Aires) - - - - - -
IMBH (Sarajevo) -1.8 -0.8 -1.9 -0.2 -0.6 -3.0 0.5 2.8 2.9
INCP (Lima) -163.8 -162.2 -153.9 -168.1 -166.8 -158.4 5.0 20.0 20.6
INM (Bogota D.C.) -14.7 -25.6 -23.8 -28.8 - -37.4 1.5 20.0 20.1
INPL (Jerusalem) 14.7 9.5 1.2 -7.7 -7.0 -10.1 0.3 7.3 7.3
INTI (Buenos Aires) -2.9 - -13.1 -41.0 -14.5 -1.9 5.0 20.0 20.6
INXE (Rio de Janeiro) -27.9 -28.0 -23.3 -19.3 -12.7 -6.1 0.3 20.0 20.0
IPQ (Caparica) 275.0 273.2 287.6 298.9 299.4 305.4 0.5 20.0 20.0
IT (Torino) 0.2 0.3 0.0 -0.2 -0.9 -1.2 0.3 1.3 1.4
JATC (Lintong) 1.5 1.1 1.4 1.5 0.7 1.2 0.3 2.9 2.9
JV (Kjeller) 18.2 21.7 9.0 2.4 8.2 2.1 0.3 4.3 4.4
KRIS (Daejeon) 5.5 5.5 5.0 4.7 4.9 5.1 0.3 3.1 3.1
LRTE (Sao Carlos) -17.1 -18.8 -11.0 -4.5 5.2 20.2 0.3 20.0 20.0
LT (Vilnius) 783.1 758.6 753.1 759.4 789.5 797.2 0.3 2.9 2.9
LUX (Belvaux) 17.1 13.3 8.5 3.5 3.5 4.6 0.3 3.0 3.0
LV (Riga) -316.3 -327.6 -311.0 -309.1 -330.9 -335.7 1.5 12.2 12.3
MASM (Bayanzurkh) -805.0 -804.5 -809.6 -803.7 -802.7 -797.8 0.4 2.8 2.8
MBM (Podgorica) 1280.9 1293.4 1320.5 1352.4 1362.5 1375.3 0.3 20.0 20.0
MIKE (Espoo) 5.2 4.7 4.2 3.6 3.3 3.0 0.3 2.7 2.7
MSL (Lower Hutt) -22.6 -34.8 -18.9 -32.1 -29.8 -35.0 1.5 20.0 20.1
NAO (Mizusawa) 245.9 249.6 257.1 266.2 273.8 277.0 2.0 20.0 20.1
NICT (Tokyo) 6.1 6.7 7.0 6.4 2.7 1.9 0.3 2.1 2.2
NIM (Beijing) 1.3 1.1 0.8 0.6 0.3 0.4 0.3 2.1 2.2
NIMB (Bucharest) -6154.5 -6512.1 -6867.9 -6833.6 -6414.1 -5989.1 0.3 7.4 7.4
NIMT (Pathumthani) - - - - - -
NIS (Cairo) - - - - - -
NIST (Boulder) 0.2 0.6 0.1 -0.4 -0.6 -0.5 0.3 2.1 2.1
NMIJ (Tsukuba) 2.2 3.2 3.5 5.0 3.7 2.7 0.3 3.3 3.3
NMLS (Sepang) -1524.2 -1495.4 -1459.9 -1438.9 -1411.6 -1381.5 1.5 3.3 3.6
NPL (Teddington) 0.9 0.1 0.0 -1.8 -1.0 -0.9 0.3 2.8 2.8
NPLI (New-Delhi) 0.2 0.1 0.0 -0.1 -0.4 0.1 0.3 2.9 2.9
NRC (Ottawa) 8.8 8.9 9.2 9.4 9.0 9.4 0.3 3.1 3.1
NRL (Washington DC) -1.8 2.4 -0.8 -1.6 2.3 -1.8 0.3 19.7 19.7
NSAI (Dublin) -199.5 -196.2 -204.8 -207.4 -210.0 -209.6 0.4 7.1 7.2
NTSC (Lintong) 0.7 0.2 -0.2 -0.9 -1.4 -1.3 0.3 2.6 2.6
ONBA (Buenos Aires) 869.3 891.7 893.3 883.8 887.9 902.2 2.0 11.2 11.4
ONRJ (Rio de Janeiro) -1.5 -1.4 -5.3 -1.5 6.8 4.9 0.4 20.0 20.0
OP (Paris) -0.2 0.1 -0.1 -0.3 0.1 0.4 0.3 1.3 1.3
ORB (Bruxelles) 0.6 0.6 1.1 0.5 0.3 0.1 0.3 2.8 2.8
PL (Warszawa) 3.4 4.5 5.1 5.6 6.1 6.8 0.4 2.9 2.9
PTB (Braunschweig) -0.8 -0.3 -0.1 -0.1 -0.1 0.2 0.1 0.8 0.8
ROA (San Fernando) -2.2 -2.0 -2.1 -2.4 -2.9 -2.4 0.3 1.4 1.4
SASO (Riyadh) -2022.1 -2031.0 -2041.6 -2049.4 -2058.8 -2072.0 0.7 3.0 3.1
SCL (Hong Kong) 71.9 79.9 76.9 78.7 78.5 64.8 1.0 3.0 3.2
SG (Singapore) -6.9 -10.1 -8.4 -14.1 -10.0 -1.3 0.3 2.8 2.8
SIQ (Ljubljana) 379.8 407.6 434.1 438.8 435.3 429.4 0.3 3.7 3.7
SL (Colombo) - - - - 66.2 60.8 0.3 2.8 2.8
SMD (Bruxelles) -5.3 -0.6 0.0 -28.0 -12.9 -13.6 0.3 3.1 3.1
SMU (Bratislava) 55.8 65.7 68.7 84.7 102.3 114.0 1.5 12.2 12.3
SP (Boras) -0.3 -0.5 -0.5 -0.7 -0.7 -0.8 0.3 1.3 1.3
SU (Moskva) 0.0 0.0 0.1 0.2 0.2 0.9 0.3 2.0 2.0
TL (Chung-Li) -0.8 -0.6 -1.4 -1.6 -1.4 -1.5 0.3 2.3 2.3
TP (Praha) 10.6 8.6 10.6 12.5 10.3 13.5 0.3 2.8 2.8
UA (Kharkov) -13.9 -9.6 -12.4 -6.2 -3.1 -8.9 3.0 7.1 7.7
UAE (Abu Dhabi) 16.2 13.0 10.4 12.0 10.1 13.4 4.0 7.6 8.6
UME (Gebze-Kocaeli) -4.5 -4.0 -4.0 -4.4 -5.0 -8.2 0.3 3.3 3.3
USNO (Washington DC) -0.7 -0.5 -0.5 -0.6 -0.5 -0.1 0.2 1.4 1.4
VMI (Ha Noi) 15.1 14.9 12.6 7.8 1.1 12.6 0.3 7.1 7.2
VSL (Delft) 2.9 0.2 -2.3 -1.2 0.7 -3.9 0.3 2.0 2.0
ZA (Pretoria) 0.2 -3.2 -1.1 3.3 6.2 5.9 0.3 2.8 2.8
- Note on section 1:
(1) IDN : Time step of UTC(IDN) of about +2500 ns on MJD 59248.25.

2 - Difference between the normalized frequencies of EAL and TAI.
Interval of validity f(EAL)-f(TAI)
Steering correction 59244 - 59269 6.501x10-13 (2021 JAN 30 - 2021 FEB 24)
New correction 59269 - 59304 6.501x10-13 (2021 FEB 24 - 2021 MAR 31)
New correction foreseen 59304 - 59334 6.501x10-13 (2021 MAR 31 - 2021 APR 30)

3 - Duration of the TAI scale interval d.

Table 1: Estimate of d by individual PSFS measurements and corresponding uncertainty.
All values are expressed in 10-15 and are valid only for the stated period of estimation.
Standard Period of d uA uB uA/Lab uB/Lab ul/Tai u uSrep Ref(uS) Ref(uB) uB(Ref) Uptime LastRep Nrep3y Steer Note
Estimation %
PTB-CS1 59244 59269 5.90 8.00 8.00 0.00 0.00 0.08 11.31 PFS/NA T148 8.00 100.0 T397 36 Y (1)
PTB-CS2 59244 59269 -5.03 5.00 12.00 0.00 0.00 0.08 13.00 PFS/NA T148 12.00 100.0 T397 35 Y (1)
IT-CsF2 59239 59269 -0.26 0.19 0.49 0.11 0.01 0.20 0.57 PFS/NA T318 0.19 95.2 T397 12 Y (2)
NRC-FCs2 59244 59269 0.23 0.13 0.31 0.10 0.00 0.23 0.42 PFS/NA T389 0.23 99.1 T397 15 Y (3)
SYRTE-FO2 59244 59269 -0.22 0.20 0.22 0.06 0.00 0.23 0.38 PFS/NA T301 0.23 92.1 T397 36 Y (4)
SYRTE-FORb 59244 59269 0.10 0.20 0.26 0.06 0.00 0.23 0.41 0.6 [1] T328 0.34 93.0 T397 37 Y (4)
PTB-CSF1 59244 59269 0.01 0.08 0.27 0.03 0.00 0.08 0.29 PFS/NA T371 0.28 94.9 T397 27 Y (5)
PTB-CSF2 59244 59269 0.00 0.13 0.17 0.04 0.00 0.08 0.23 PFS/NA T370 0.17 91.0 T397 39 Y (5)
SU-CsFO2 59244 59269 -0.16 0.25 0.22 0.13 0.00 0.23 0.43 PFS/NA T315 0.50 64.4 T397 31 Y (6)
NMIJ-Yb1 59179 59194 0.06 0.01 0.22 0.10 0.10 0.37 0.45 0.5 [1] T392 0.36 93.3 T396 12 Y (7)

Notes:
(1) Continuously operating as a clock participating to TAI
(2) Report 05 MAR. 2021 by INRIM
(3) Report 03 MAR. 2021 by NRC
(4) Report 02 MAR. 2021 by LNE-SYRTE
(5) Report 02 MAR. 2021 by PTB
(6) Report 26 FEB. 2021 by SU
(7) Corrected values and report from NMIJ on 05 MAR. 2021. Replaces values published in Circular T 396.
[1] CCTF Recommendation 2 (2017) : Updates to the CIPM list of standard frequencies in Consultative
Committee for Time and Frequency Report of the 21st meeting (2017), 2017, 56 p.

Table 2: Estimate of d by the BIPM based on all PSFS measurements identified to be used for TAI steering
over the period MJD 58884-59269, and corresponding uncertainties.

Period of estimation d u
59244-59269 -0.03x10-15 0.13x10-15 (2021 JAN 30 - 2021 FEB 24)

4 - Relations of UTC and TAI with predictions of UTC(k) disseminated by GNSS.

[UTC-UTC(USNO)_GPS] = C0', [TAI-UTC(USNO)_GPS] = 37 s + C0'
[UTC-UTC(SU)_GLONASS]= C1', [TAI-UTC(SU)_GLONASS]= 37 s + C1'

For this edition of Circular T, σ0'= 0.6 ns, σ1'= 6.5 ns

2021 0h UTC MJD C0'/ns N0 C1'/ns N1'
JAN 30 59244 2.9 89 20.1 85
JAN 31 59245 2.8 90 22.7 87
FEB 1 59246 2.5 89 21.7 88
FEB 2 59247 2.3 79 21.3 86
FEB 3 59248 2.2 10 22.3 88
FEB 4 59249 2.8 90 18.9 90
FEB 5 59250 3.0 89 15.9 87
FEB 6 59251 2.0 89 17.1 87
FEB 7 59252 1.9 89 18.6 85
FEB 8 59253 2.5 90 18.3 89
FEB 9 59254 1.8 89 17.2 86
FEB 10 59255 1.3 89 16.3 89
FEB 11 59256 0.7 89 15.9 89
FEB 12 59257 1.4 90 15.6 90
FEB 13 59258 2.0 89 14.1 82
FEB 14 59259 3.2 89 13.3 88
FEB 15 59260 4.0 89 12.5 89
FEB 16 59261 3.7 90 14.4 88
FEB 17 59262 4.3 89 18.7 79
FEB 18 59263 3.1 89 19.8 89
FEB 19 59264 1.6 89 20.9 89
FEB 20 59265 1.4 90 22.3 90
FEB 21 59266 0.8 89 21.1 88
FEB 22 59267 0.6 89 18.6 89
FEB 23 59268 0.7 89 19.2 89
FEB 24 59269 0.1 90 19.1 76

5 - Time links used for the computation of TAI, calibrations information and corresponding uncertainties.

Link Type Equipment Cal_ID1 / Cal_ID2 uStb/ns uCal/ns uAg/ns Al/ns YYMM
AOS /PTB GPSPPP AO_4 /PT13 1014-2018 / 1001-2018 0.3 2.8 1.2
APL /PTB GPSPPP AP04 /PT13 NC / 1001-2018 0.3 20.0
AUS /PTB GPSPPP AU04 /PT13 1002-2010 / 1001-2018 0.3 11.2 10.0
BEV /PTB GPSPPP BE1_ /PT13 1012-2016 / 1001-2018 0.3 3.2 2.0
BFKH/PTB GPS MC MK01 /PT13 NC / 1001-2018 1.5 20.0
BIM /PTB GPSPPP BM51 /PT13 2007-2019 / 1001-2018 0.7 7.1 0.9
BIRM/PTB GPS P3 BI22 /PT13 1016-2018 / 1001-2018 0.7 2.7 0.9
BOM /PTB GPS MC MABM /PT13 NA_Al / 1001-2018 5.0 7.5 2.6 +4.4 2003
BY /PTB GPS MC BY46 /PT13 2001-2008 / 1001-2018 1.5 12.2 10.0
CAO /PTB GPS MC CA__ /PT13 NC / 1001-2018 1.5 20.0
CNES/PTB GPSPPP CS21 /PT13 1015-2018 / 1001-2018 0.3 2.8 1.3
CNM /PTB GPS MC CN00 /PT13 NA_Al / 1001-2018 4.0 11.2 10.0 -27.3 0804
CNMP/PTB GPS P3 MP1_ /PT13 NA_Al / 1001-2018 0.7 7.3 2.2 41.7 1807
DFNT/PTB GPS MC DN__ /PT13 NC / 1001-2018 1.5 20.0
DLR NL
DMDM/PTB GPSPPP ZM68 /PT13 1011-2016 / 1001-2018 0.3 3.2 2.0
DTAG/PTB GPSPPP DT05 /PT13 1012-2019 / 1001-2018 0.3 2.7 0.9
EIM /PTB GPS MC EI__ /PT13 NA / 4.0 11.2 10.0
ESTC/PTB GPSPPP ES07 /PT13 1013-2020 / 1001-2018 0.3 2.7 0.9
HKO /PTB GPSPPP HKO2 /PT13 1011-2018 / 1001-2018 0.5 2.9 1.4
ICE /PTB GPS MC CE1_ /PT13 NC / 1001-2018 2.5 20.0
IDN /PTB GPSPPP KI01 /PT13 1017-2018 / 1001-2018 0.3 2.7 1.0
IFAG/PTB GPSPPP IF14 /PT13 1016-2017 / 1001-2018 0.3 3.1 1.5
IGNA/PTB NL
IMBH/PTB GPSPPP BH02 /PT13 1011-2019 / 1001-2018 0.5 2.7 0.9
INCP/PTB GPS MC CP__ /PT13 NC / 1001-2018 5.0 20.0
INM /PTB GPS MC IC__ /PT13 NC / 1001-2018 1.5 20.0
INPL/PTB GPSPPP IL06 /PT13 2003-2016 / 1001-2018 0.3 7.3 1.9
INTI/PTB GPS MC INTI /PT13 NC / 1001-2018 5.0 20.0
INXE/PTB GPSPPP NXRA /PT13 NC / 1001-2018 0.3 20.0
IPQ /PTB GPSPPP IP05 /PT13 NC / 1001-2018 0.5 20.0
JATC/PTB GPSPPP JA01 /PT13 1201-2018 / 1001-2018 0.3 2.8 1.2
JV /PTB GPSPPP JV02 /PT13 1101-2017 / 1001-2018 0.3 4.3 1.5
KRIS/PTB GPSPPP KRG1 /PT13 1017-2017 / 1001-2018 0.3 3.0 1.7
LRTE/PTB GPSPPP LRRC /PT13 NC / 1001-2018 0.3 20.0
LT /PTB GPSPPP LT02 /PT13 1014-2018 / 1001-2018 0.3 2.8 1.2
LUX /PTB GPSPPP LU01 /PT13 1012-2018 / 1001-2018 0.3 2.9 1.4
LV /PTB GPS MC LV01 /PT13 2001-2007 / 1001-2018 1.5 12.2 10.0
MASM/PTB GPSPPP MN__ /PT13 1019-2018 / 1001-2018 0.4 2.7 1.1
MBM /PTB GPSPPP ME01 /PT13 NC / 1001-2018 0.3 20.0
MIKE/PTB GPSPPP MI04 /PT13 1016-2019 / 1001-2018 0.3 2.7 0.9
MSL /PTB GPS P3 MS0_ /PT13 NC / 1001-2018 1.5 20.0
NAO /PTB GPS MC NAT2 /PT13 NC / 1001-2018 2.0 20.0
NICT/PTB GPSPPP NC4S /PT13 1001-2018 / 1001-2018 0.3 2.1 1.3
NIM /PTB GPSPPP IM06 /PT13 1001-2018 / 1001-2018 0.3 2.1 1.2
NIMB/PTB GPSPPP MB02 /PT13 NA_Al / 1001-2018 0.3 7.4 2.4 32.2 1611
NIMT NL
NIS /PTB NL
NMIJ/PTB GPSPPP NM0D /PT13 1001-2014 / 1001-2018 0.3 3.2 2.7
NMLS/PTB GPS MC LSM1 /PT13 1013-2017 / 1001-2018 1.5 3.2 1.8
NPL /PTB GPSPPP NPL2 /PT13 1015-2019 / 1001-2018 0.3 2.7 0.9
NPLI/PTB GPSPPP LI2P /PT13 1013-2018 / 1001-2018 0.3 2.9 1.4
NRC /PTB GPSPPP NRC4 /PT13 1019-2017 / 1001-2018 0.3 3.0 1.6
NRL /PTB GPSPPP RL2_ /PT13 NC / 1001-2018 0.3 20.0
NSAI/PTB GPSPPP IE01 /PT13 2022-2019 / 1001-2018 0.4 7.1 0.9
NTSC/PTB GPSPPP NTP1 /PT13 1001-2016 / 1001-2018 0.3 2.6 2.0
ONBA/PTB GPS MC ON__ /PT13 1002-2004 / 1001-2018 2.0 11.2 10.0
ONRJ/PTB GPSPPP RJ03 /PT13 NC_Al / 1001-2018 0.4 20.0 -11.7 1912
ORB /PTB GPSPPP OR5Z /PT13 1011-2020 / 1001-2018 0.3 2.7 0.9
PL /PTB GPSPPP PL_3 /PT13 1014-2018 / 1001-2018 0.4 2.8 1.2
SASO/PTB GPSPPP SAS0 /PT13 1020-2017 / 1001-2018 0.7 2.9 1.5
SCL /PTB GPS P3 SC05 /PT13 1011-2018 / 1001-2018 1.0 2.9 1.4
SG /PTB GPSPPP SG01 /PT13 1019-2018 / 1001-2018 0.3 2.7 1.0
SIQ /PTB GPSPPP SI01 /PT13 1013-2019 / 1001-2018 0.3 3.6 0.9
SL /PTB GPSPPP SL01 /PT13 1017-2018 / 1001-2018 0.3 2.7 0.9
SMD /PTB GPSPPP SD01 /PT13 1014-2017 / 1001-2018 0.3 3.0 1.7
SMU /PTB GPS MC SM00 /PT13 NA_Al / 1001-2018 1.5 12.2 10.0 57.8 0908
SU /PTB GPSPPP SU31 /PT13 1001-2018 / 1001-2018 0.3 2.1 1.3
TL /PTB GPSPPP TLT1 /PT13 1001-2018 / 1001-2018 0.3 2.2 1.3
TP /PTB GPSPPP TP02 /PT13 1015-2019 / 1001-2018 0.3 2.7 0.9
UA /PTB GPS MC UA05 /PT13 2003-2018 / 1001-2018 3.0 7.1 1.2
UAE /PTB GPS MC AE__ /PT13 2001-2016 / 1001-2018 4.0 7.6 2.9
UME /PTB GPSPPP UM01 /PT13 1011-2016 / 1001-2018 0.3 3.2 2.1
VMI /PTB GPSPPP VM02 /PT13 2001-2019 / 1001-2018 0.3 7.1 0.9
ZA /PTB GPSPPP ZA02 /PT13 1018-2018 / 1001-2018 0.3 2.7 1.1
Link Type Equipment Cal_ID uStb/ns uCal/ns uAg/ns Al/ns YYMM
CH /PTB TWGPPP CH01 /PTB05 0284-2012 0.3 2.4 2.0
IT /PTB TWGPPP IT02 /PTB05 0502-2019 0.3 1.1 0.4
NIST/PTB TWGPPP NIST01/PTB05 0393-2015 0.3 2.0 1.5
OP /PTB TWSDRR OP51 /PTB55 0517-2020 0.3 1.1 0.3
ROA /PTB TWGPPP ROA01 /PTB05 0504-2019 0.3 1.1 0.4
SP /PTB TWGPPP SP01 /PTB05 0496-2019 0.3 1.1 0.4
USNO/PTB TWGPPP USNO01/PTB05 0395-2016 0.3 1.7 1.2
VSL /PTB TWGPPP VSL01 /PTB05 0295-2015 0.3 1.8 1.3