Club Certificate2025
EMERALDEST 221
Estonian Yachting Union
Purje 8, maja 3
11911 Tallinn
Estonia
Rated boat velocities in knots
Wind Velocity 4 kt 6 kt 8 kt 10 kt 12 kt 14 kt 16 kt 20 kt 24 kt
Beat Angles43.3°43.3°40.9°39.6°38.6°38.2°37.8°37.6°38.2°
Beat VMG2.413.324.034.534.834.975.065.125.09
52°3.775.055.956.526.836.997.077.157.17
60°3.995.316.186.717.007.177.267.367.39
75°4.115.456.346.857.157.377.527.717.81
90°3.945.366.386.967.257.437.658.008.21
110°3.965.426.507.097.467.778.038.358.54
120°3.805.246.337.017.427.788.128.709.05
135°3.364.705.806.647.177.567.958.729.57
150°2.763.985.096.026.747.207.578.319.13
Run VMG2.393.454.415.235.956.547.007.698.38
Gybe Angles146.0°146.0°150.5°153.4°159.4°166.0°173.2°177.2°177.2°
APH ToD:579.0CDL: 8.783APH ToT: 1.0363CertNo:045/21
BOAT
ClassRidas 35DesignerLonngren/RidasBuilderRidas JahtAge date06/1997Series date06/1997Offset fileRIDAS35.OFFData fileEST221
HULL
Length Overall10.594 mMaximum Beam3.398 mDraft1.978 mDisplacement5,931 kgDLR6.6877IMS DivisionCruiser/RacerDynamic Allowance0.260%Age Allowance0.487%
PROPELLER
InstallationStrutTypeFolding 3 bladesDiameter0.410m
CREW
Maximum weight600 kg(declared)Minimum weight470 kg ✱ when appliedNon Manual PowerNoCrew Arm Extension
SAIL AREAS (m²)
MeasuredRatedMainsail33.5033.91Headsail Luffed32.0032.00Headsail FlyingSymmetric85.9285.92Asymmetric
STORM SAIL AREAS (m²)
Trysail10.23Storm Jib9.68Heavy Weather Jib26.12
SAIL LIMITS
Headsails5Spinnakers4
STABILITY
Righting MomentN/AStability IndexN/A
The owner and any other person in charge is responsible that boat is complying with her certificate in accordance with RRS 78.1 and ORC Rule 304.
Club Certificate2025
EMERALDEST 221
Estonian Yachting Union
Purje 8, maja 3
11911 Tallinn
Estonia
Time Allowances in secs/NM
Wind Velocity 4 kt 6 kt 8 kt 10 kt 12 kt 14 kt 16 kt 20 kt 24 kt
Beat VMG1493.21084.1893.2794.7745.7724.1712.0702.6706.8
52°955.8712.6604.9551.8526.8514.9509.2503.3502.3
60°902.0678.4582.1536.7514.2502.3496.0489.1487.0
75°876.3660.1567.8525.3503.2488.8478.5467.0461.1
90°912.8672.1564.7517.5496.6484.5470.4449.9438.3
110°909.0664.0554.1507.5482.4463.1448.2430.9421.6
120°946.3687.3568.6513.7485.1462.9443.6414.0397.7
135°1071.1766.3620.4541.8502.0476.1453.1413.0376.2
150°1305.5903.8707.0597.9534.2499.7475.5433.0394.2
Run VMG1507.91043.6816.1687.8604.7550.3514.6468.0429.8
Selected Courses
Windward / Leeward1499.21063.8854.6741.2675.2637.2613.3585.3568.3
All purpose1137.1821.6674.0598.6557.7534.3517.9496.1482.2
Single Number Scoring Options
CourseTime On
Distance
Time On
Time
Windward / Leeward707.50.8481
All purpose579.01.0363
 
Custom scoring options for Australia
Scoring OptionTime On
Distance
Time On
Time
Triple Number Coastal/Long Distance Low747.80.8024
Triple Number Coastal/Long Distance Medium575.21.0432
Triple Number Coastal/Long Distance High513.81.1677
Triple Number Windward/Leeward Low959.20.6255
Triple Number Windward/Leeward Medium702.70.8539
Triple Number Windward/Leeward High608.80.9856
Custom scoring options for Austria
Scoring OptionTime On
Distance
Time On
Time
Coastal/Long Distance629.20.9537
Triple Number Coastal/Long Distance Low747.80.8024
Triple Number Coastal/Long Distance Medium575.21.0432
Triple Number Coastal/Long Distance High513.81.1677
Triple Number Windward/Leeward Low959.20.6255
Triple Number Windward/Leeward Medium702.70.8539
Triple Number Windward/Leeward High608.80.9856
Performance Curve4 kt 6 kt 8 kt 10 kt 12 kt 14 kt 16 kt 20 kt 24 kt
Coastal/Long Distance1590.21061.8804.8670.9594.1554.2523.7476.1461.9
Custom scoring options for Brazil
Scoring OptionTime On
Time
Upwind "bolina"0.7425
Downwind "popa"0.8965
70% up, 30% down "Ilhabela"0.7829
30% up, 70% down "Ilhabela-inverso"0.8440
Custom scoring options for Bulgaria
Scoring OptionTime On
Distance
Time On
Time
Triple Number Coastal/Long Distance Low747.80.8024
Triple Number Coastal/Long Distance Medium575.21.0432
Triple Number Coastal/Long Distance High513.81.1677
Triple Number Windward/Leeward Low959.20.6255
Triple Number Windward/Leeward Medium702.70.8539
Triple Number Windward/Leeward High608.80.9856
Predominantly Upwind626.20.9581
Predominantly Downwind588.01.0204
Custom scoring options for Canada
Scoring OptionTODTOT
Triple Number AP Low747.80.8024
Triple Number AP Medium575.21.0431
Triple Number AP High513.81.1677
Triple Number Windward/Leeward Low1002.00.5988
Triple Number Windward/Leeward Medium702.70.8539
Triple Number Windward/Leeward High608.80.9856
Single Number Predominant Upwind651.40.9211
Single Number Predominant Reaching579.01.0363
Single Number Predominant Downwind614.50.9764
Predominant Upwind - Low900.90.6660
Predominant Upwind - Low/Med688.10.8720
Predominant Upwind - Medium605.50.9908
Predominant Upwind - Med/High564.81.0622
Predominant Upwind - High547.81.0954
Predominant Downwind Low906.00.6623
Predominant Downwind Low/Med667.50.8989
Predominant Downwind Medium566.41.0593
Predominant Downwind Med/High505.11.1879
Predominant Downwind High470.41.2755
Predominant Reaching Low807.40.7431
Predominant Reaching Low/Med614.80.9759
Predominant Reaching Medium539.81.1115
Predominant Reaching Med/High497.21.2068
Predominant Reaching High472.01.2711
SA/DSPL Upwind19.87SA/DSPL Downwind36.23
Scoring OptionTODTOT
5-Band Windward/Leeward Low1120.70.5354
5-Band Windward/Leeward Low/Med819.00.7326
5-Band Windward/Leeward Medium689.60.8701
5-Band Windward/Leeward Med/High617.80.9712
5-Band Windward/Leeward High587.21.0218
Windward/Leeward 60-40 Low1124.30.5337
Windward/Leeward 60-40 Low/Med828.10.7245
Windward/Leeward 60-40 Medium703.60.8527
Windward/Leeward 60-40 Med/High637.30.9415
Windward/Leeward 60-40 High610.80.9824
5-Band AP Low827.60.7250
5-Band AP Low/Med652.00.9203
5-Band AP Medium567.01.0583
5-Band AP Med/High520.41.1531
5-Band AP High497.51.2061
5-Band SF Bay Tour - Low965.90.6212
5-Band SF Bay Tour - Low/Med784.00.7653
5-Band SF Bay Tour - Medium667.40.8990
5-Band SF Bay Tour - Med/High604.60.9924
5-Band SF Bay Tour - High576.91.0401
Chicago-Mac Upwind0.8926
Chicago-Mac All Purpose0.9193
Chicago-Mac Downwind0.9407
Bayview-Mac Cove Island0.6712
Bayview-Mac Shore0.6760
Harvest Moon Regatta504.91.1883
Custom scoring options for Cyprus
Scoring OptionTime On
Distance
Time On
Time
Coastal/Long Distance629.20.9537
Triple Number Coastal/Long Distance Low747.80.8024
Triple Number Coastal/Long Distance Medium575.21.0432
Triple Number Coastal/Long Distance High513.81.1677
Triple Number Windward/Leeward Low959.20.6255
Triple Number Windward/Leeward Medium702.70.8539
Triple Number Windward/Leeward High608.80.9856
Performance Curve4 kt 6 kt 8 kt 10 kt 12 kt 14 kt 16 kt 20 kt 24 kt
Coastal/Long Distance1590.21061.8804.8670.9594.1554.2523.7476.1461.9
Custom scoring options for Denmark
Scoring OptionTime On
Distance
Time On
Time
Coastal/Long Distance629.20.9537
Triple Number Coastal/Long Distance Low747.80.8024
Triple Number Coastal/Long Distance Medium575.21.0432
Triple Number Coastal/Long Distance High513.81.1677
Triple Number Windward/Leeward Low959.20.6255
Triple Number Windward/Leeward Medium702.70.8539
Triple Number Windward/Leeward High608.80.9856
Performance Curve4 kt 6 kt 8 kt 10 kt 12 kt 14 kt 16 kt 20 kt 24 kt
Coastal/Long Distance1590.21061.8804.8670.9594.1554.2523.7476.1461.9
Custom scoring options for Spain
Scoring OptionTime On
Distance
Coastal/Long Distance629.2
Performance Curve4 kt 6 kt 8 kt 10 kt 12 kt 14 kt 16 kt 20 kt 24 kt
Coastal/Long Distance1590.21061.8804.8670.9594.1554.2523.7476.1461.9
Custom scoring options for Estonia
Scoring OptionTime On
Distance
Time On
Time
Triple Number Coastal/Long Distance Low747.80.8024
Triple Number Coastal/Long Distance Medium575.21.0432
Triple Number Coastal/Long Distance High513.81.1677
Triple Number Windward/Leeward Low959.20.6255
Triple Number Windward/Leeward Medium702.70.8539
Triple Number Windward/Leeward High608.80.9856
Custom scoring options for Finland
Scoring OptionTime On
Distance
Time On
Time
FinRating629.20.9537
FinRating, kevyt tuuli1101.90.9075
FinRating, kova tuuli500.90.9983
Custom scoring options for France
Scoring OptionTime On
Distance
Time On
Time
Triple Number Coastal/Long Distance Low747.80.8024
Triple Number Coastal/Long Distance Medium575.21.0432
Triple Number Coastal/Long Distance High513.81.1677
Triple Number Windward/Leeward Low959.20.6255
Triple Number Windward/Leeward Medium702.70.8539
Triple Number Windward/Leeward High608.80.9856
Custom scoring options for Germany
Scoring OptionTime On
Time
Coastal/Long Distance0.9537
Triple Number Coastal/Long Distance Low0.8024
Triple Number Coastal/Long Distance Medium1.0432
Triple Number Coastal/Long Distance High1.1677
Triple Number Windward/Leeward Low0.6255
Triple Number Windward/Leeward Medium0.8539
Triple Number Windward/Leeward High0.9856
Performance Curve4 kt 6 kt 8 kt 10 kt 12 kt 14 kt 16 kt 20 kt 24 kt
Coastal/Long Distance1590.21061.8804.8670.9594.1554.2523.7476.1461.9
For information
General Purpose Handicap (GPH)650.6
Custom scoring options for Greece
Scoring OptionTime On
Distance
Time On
Time
Coastal/Long Distance629.20.9537
Triple Number Coastal/Long Distance Low747.80.8024
Triple Number Coastal/Long Distance Medium575.21.0432
Triple Number Coastal/Long Distance High513.81.1677
Triple Number Windward/Leeward Low959.20.6255
Triple Number Windward/Leeward Medium702.70.8539
Triple Number Windward/Leeward High608.80.9856
Performance Curve4 kt 6 kt 8 kt 10 kt 12 kt 14 kt 16 kt 20 kt 24 kt
Coastal/Long Distance1590.21061.8804.8670.9594.1554.2523.7476.1461.9
Custom scoring options for Hungary
Scoring OptionTime On
Distance
Time On
Time
Triple Number Coastal/Long Distance Low747.80.8024
Triple Number Coastal/Long Distance Medium575.21.0432
Triple Number Coastal/Long Distance High513.81.1677
Triple Number Windward/Leeward Low959.20.6255
Triple Number Windward/Leeward Medium702.70.8539
Triple Number Windward/Leeward High608.80.9856
Custom scoring options for Israel
Scoring OptionTime On
Distance
Time On
Time
Coastal/Long Distance629.20.9537
Triple Number Coastal/Long Distance Low747.80.8024
Triple Number Coastal/Long Distance Medium575.21.0432
Triple Number Coastal/Long Distance High513.81.1677
Triple Number Windward/Leeward Low959.20.6255
Triple Number Windward/Leeward Medium702.70.8539
Triple Number Windward/Leeward High608.80.9856
Performance Curve4 kt 6 kt 8 kt 10 kt 12 kt 14 kt 16 kt 20 kt 24 kt
Coastal/Long Distance1590.21061.8804.8670.9594.1554.2523.7476.1461.9
Custom scoring options for Japan
Scoring OptionTime On
Distance
Time On
Time
Coastal/Long Distance629.20.9537
Triple Number Coastal/Long Distance Low747.80.8024
Triple Number Coastal/Long Distance Medium575.21.0432
Triple Number Coastal/Long Distance High513.81.1677
Triple Number Windward/Leeward Low959.20.6255
Triple Number Windward/Leeward Medium702.70.8539
Triple Number Windward/Leeward High608.80.9856
Performance Curve4 kt 6 kt 8 kt 10 kt 12 kt 14 kt 16 kt 20 kt 24 kt
Coastal/Long Distance1590.21061.8804.8670.9594.1554.2523.7476.1461.9
Custom scoring options for Korea
Scoring OptionTime On
Distance
Triple Number Coastal/Long Distance Low747.8
Triple Number Coastal/Long Distance Medium575.2
Triple Number Coastal/Long Distance High513.8
Triple Number Windward/Leeward Low959.2
Triple Number Windward/Leeward Medium702.7
Triple Number Windward/Leeward High608.8
Predominantly Upwind626.2
Predominantly Downwind588.0
Predominantly Reaching565.4
Custom scoring options for Lithuania
Scoring OptionTime On
Distance
Time On
Time
Coastal/Long Distance629.20.9537
Triple Number Coastal/Long Distance Low747.80.8024
Triple Number Coastal/Long Distance Medium575.21.0432
Triple Number Coastal/Long Distance High513.81.1677
Triple Number Windward/Leeward Low959.20.6255
Triple Number Windward/Leeward Medium702.70.8539
Triple Number Windward/Leeward High608.80.9856
Performance Curve4 kt 6 kt 8 kt 10 kt 12 kt 14 kt 16 kt 20 kt 24 kt
Coastal/Long Distance1590.21061.8804.8670.9594.1554.2523.7476.1461.9
Custom scoring options for Netherlands
Scoring OptionTime On
Time
Triple Number Coastal/Long Distance Low0.8024
Triple Number Coastal/Long Distance Medium1.0432
Triple Number Coastal/Long Distance High1.1677
Triple Number Windward/Leeward Low0.6255
Triple Number Windward/Leeward Medium0.8539
Triple Number Windward/Leeward High0.9856
Coastal/Long Distance0.9537
Predominantly Upwind0.9581
Predominantly Downwind1.0204
For information
General Purpose Handicap (GPH)650.6
Custom scoring options for Norway
Scoring OptionTime On
Time
Distanseseilas Singeltall  (APH)1.0363
Distanseseilas Trippeltall svak vind0.8024
Distanseseilas Trippeltall mellomvind1.0432
Distanseseilas Trippeltall sterk vind1.1677
Pølsebane Trippeltall svak vind0.6255
Pølsebane Trippeltall mellomvind0.8539
Pølsebane Trippeltall sterk vind0.9856
Motvind Singeltall0.9581
Medvind Singeltall1.0204
Custom scoring options for Portugal
Scoring OptionTime On
Distance
Time On
Time
Triple Number Coastal/Long Distance Low747.80.8024
Triple Number Coastal/Long Distance Medium575.21.0432
Triple Number Coastal/Long Distance High513.81.1677
Triple Number Windward/Leeward Low959.20.6255
Triple Number Windward/Leeward Medium702.70.8539
Triple Number Windward/Leeward High608.80.9856
Coastal/Long Distance629.20.9537
Custom scoring options for Russia
Scoring OptionTime On
Distance
Time On
Time
Predominantly Upwind626.20.9581
Predominantly Downwind588.01.0204
Custom scoring options for South Africa
Scoring OptionTime On
Distance
Time On
Time
Cape Doctor Inshore573.41.0463
Cape Doctor Coastal486.41.2336
Triple Number Coastal/Long Distance Low747.80.8024
Triple Number Coastal/Long Distance Medium575.21.0432
Triple Number Coastal/Long Distance High513.81.1677
Triple Number Windward/Leeward Low959.20.6255
Triple Number Windward/Leeward Medium702.70.8539
Triple Number Windward/Leeward High608.80.9856
Custom scoring options for Slovenia
Scoring OptionTime On
Time
Triple Number Coastal/Long Distance Low0.8024
Triple Number Coastal/Long Distance Medium1.0432
Triple Number Coastal/Long Distance High1.1677
Triple Number Windward/Leeward Low0.6255
Triple Number Windward/Leeward Medium0.8539
Triple Number Windward/Leeward High0.9856
Custom scoring options for Switzerland
Scoring OptionTime On
Time
Triple Number Coastal/Long Distance Low0.8024
Triple Number Coastal/Long Distance Medium1.0432
Triple Number Coastal/Long Distance High1.1677
Triple Number Windward/Leeward Low0.6255
Triple Number Windward/Leeward Medium0.8539
Triple Number Windward/Leeward High0.9856
Custom scoring options for Sweden
Scoring OptionTime On
Distance
Time On
Time
Coastal/Long Distance629.20.9537
Triple Number Coastal/Long Distance Low747.80.8024
Triple Number Coastal/Long Distance Medium575.21.0432
Triple Number Coastal/Long Distance High513.81.1677
Triple Number Windward/Leeward Low959.20.6255
Triple Number Windward/Leeward Medium702.70.8539
Triple Number Windward/Leeward High608.80.9856
Predominantly Upwind626.20.9581
Predominantly Downwind588.01.0204
Performance Curve4 kt 6 kt 8 kt 10 kt 12 kt 14 kt 16 kt 20 kt 24 kt
Coastal/Long Distance1590.21061.8804.8670.9594.1554.2523.7476.1461.9
Custom scoring options for Ukraine
Scoring OptionTime On
Distance
Time On
Time
Coastal/Long Distance629.20.9537
Triple Number Coastal/Long Distance Low747.80.8024
Triple Number Coastal/Long Distance Medium575.21.0432
Triple Number Coastal/Long Distance High513.81.1677
Triple Number Windward/Leeward Low959.20.6255
Triple Number Windward/Leeward Medium702.70.8539
Triple Number Windward/Leeward High608.80.9856
Performance Curve4 kt 6 kt 8 kt 10 kt 12 kt 14 kt 16 kt 20 kt 24 kt
Coastal/Long Distance1590.21061.8804.8670.9594.1554.2523.7476.1461.9
Custom scoring options for United States of America
Scoring OptionTODTOT
Triple Number AP Low747.80.8024
Triple Number AP Medium575.21.0431
Triple Number AP High513.81.1677
Triple Number Windward/Leeward Low1002.00.5988
Triple Number Windward/Leeward Medium702.70.8539
Triple Number Windward/Leeward High608.80.9856
Single Number Predominant Upwind651.40.9211
Single Number Predominant Reaching579.01.0363
Single Number Predominant Downwind614.50.9764
Predominant Upwind - Low900.90.6660
Predominant Upwind - Low/Med688.10.8720
Predominant Upwind - Medium605.50.9908
Predominant Upwind - Med/High564.81.0622
Predominant Upwind - High547.81.0954
Predominant Downwind Low906.00.6623
Predominant Downwind Low/Med667.50.8989
Predominant Downwind Medium566.41.0593
Predominant Downwind Med/High505.11.1879
Predominant Downwind High470.41.2755
Predominant Reaching Low807.40.7431
Predominant Reaching Low/Med614.80.9759
Predominant Reaching Medium539.81.1115
Predominant Reaching Med/High497.21.2068
Predominant Reaching High472.01.2711
SA/DSPL Upwind19.87SA/DSPL Downwind36.23
Scoring OptionTODTOT
5-Band Windward/Leeward Low1120.70.5354
5-Band Windward/Leeward Low/Med819.00.7326
5-Band Windward/Leeward Medium689.60.8701
5-Band Windward/Leeward Med/High617.80.9712
5-Band Windward/Leeward High587.21.0218
Windward/Leeward 60-40 Low1124.30.5337
Windward/Leeward 60-40 Low/Med828.10.7245
Windward/Leeward 60-40 Medium703.60.8527
Windward/Leeward 60-40 Med/High637.30.9415
Windward/Leeward 60-40 High610.80.9824
5-Band AP Low827.60.7250
5-Band AP Low/Med652.00.9203
5-Band AP Medium567.01.0583
5-Band AP Med/High520.41.1531
5-Band AP High497.51.2061
5-Band SF Bay Tour - Low965.90.6212
5-Band SF Bay Tour - Low/Med784.00.7653
5-Band SF Bay Tour - Medium667.40.8990
5-Band SF Bay Tour - Med/High604.60.9924
5-Band SF Bay Tour - High576.91.0401
Chicago-Mac Upwind0.8926
Chicago-Mac All Purpose0.9193
Chicago-Mac Downwind0.9407
Bayview-Mac Cove Island0.6712
Bayview-Mac Shore0.6760
Harvest Moon Regatta504.91.1883
Club Certificate2025
EMERALDEST 221
Estonian Yachting Union
Purje 8, maja 3
11911 Tallinn
Estonia
Data in meters/kilograms (Metric)
HULL AND APPENDAGES (Lightship Trim)
ClassRidas 35Measurement08/07/2005HINPlan reviewHull constructionSolidCarbon rudderNoLight stanchionsNoTrim tabNo
LOA10.594Max. Beam3.398Draft1.978Displacement5,931Wetted area25.62IMS L9.546LSM09.607Acc. length10.594Sink (kg/mm) 19.49
VCGD0.070VCGM0.076RM Rated (kg·m) 120.5Limit of positive stability(°) N/AStability IndexN/ADefault crew weight650Declared crew weight600
PROPELLER
Propeller TypeFolding 3 blades
InstallationStrutTwin screwNoHydro generatorNo
PRD0.410PBW0.111PIPA0.0029
EDL1.520ST10.050ST20.170
ST30.170ST40.090ST50.290
RIG
Forestay tensionAftInner stayFixedMast materialAluminumSingle headsail furlerNoMainsail furlerNoArticulated bowspritNoNon-circular riggingNoFiber riggingNoAdjustable mast footNoRunning backstays1CheckstaysSpreaders2Rotating mastNo
P13.880IG13.908ISP14.068MDT10.125MDL10.185MDT20.117MDL20.178TL0.000MW0.000GO0.000
E4.210J4.250BAS1.427FSDFoilSFJ0.150SPL4.290WPLTPS4.730BDMWTMCG
Flying Headsail Foretriangles IdISPTPS
FLOTATION AND STABILITY
Calculation methodVCG entered directlyVCG entered0.070Flotation Date12/05/2021
BALLAST
TANKS
INVENTORY
INVENTORY
Fixed Ballast Total0
Total deductible
Total deductible
Club Certificate2025
EMERALDEST 221
Estonian Yachting Union
Purje 8, maja 3
11911 Tallinn
Estonia
MAINSAIL
IdMHBMUWMTWMHWMQWAreaMeas.DateComment2a0.130.851.512.543.4233.5014/05/202210.140.811.472.543.3433.0601/04/2020
HEADSAIL
IdHHBHUWHTWHHWHQWHLPHLUBtnFlyingFTAreaMeas.DateComment30.120.791.422.463.434.4113.46NoNo 32.0012/08/201820.060.500.981.993.084.1613.87NoNo 28.3207/05/2021
SYMMETRIC SPINNAKER
IdSLUSLESLSHWSFLAreaMeas.DateComment213.9913.9913.997.407.2585.9230/04/2006113.9213.9213.927.206.6882.3101/04/2020
CRUISER/RACER REQUIREMENTS*
Accommodation length10.6 mTable area0.44 m²Headroom1.74 mMinimum number of berths4Personal gear stowage0.16 m³Fresh water capacity92 lMinimum number of seats in cockpit4Food stowage0.24 m³Fuel capacity62 lCabin soleStovesSinksGalley gear stowageToiletWash basinNavigation areaHanging locker
*This list is a summary of the requirements. See IMS Appendix 1 for details.