Time Zone Boundaries V2015 User Guide

TimeZoneInfo with DST Rules

Table of Contents

Introduction ...... 3 Overview ...... 3 Applications...... 4 Background and Reference Information ...... 5 Data Source and Methodology ...... 5 National Sovereign Territory ...... 5 Map Depiction of Territorial Waters ...... 6 Frequency of Data Updates ...... 7 Data Descriptions ...... 8 Time Zones Table ...... 8 Table Format ...... 8 DST Rules Table ...... 10 Table Format ...... 10 Date Rule Formats...... 11

Introduction

Overview Stopwatch Data’s TimeZoneInfo with DST Rules is

 A map of the World’s observed time zones (TimeZones file), and

 A collection of the rules and decrees by which Daylight Saving Time (DST) is honored (DST Rules file).

Mapped Geographies

Regarding landmasses, the TimeZone map depicts individual countries within their respective TimeZone. Individual countries are further subdivided, when multiple TimeZones and/or DST rules are observed. These landmass TimeZone boundaries have incorporated the territorial waters (typically twelve miles beyond each shoreline), since this area is regarded as sovereign territory of a state/country.

Regarding the oceans/waters, the TimeZone map includes boundaries for each of the twenty-five nautical time zones. This completes timezone coverage over the entire globe.

Rules and Decrees

The attribute data for each boundary includes the offset in hours from Universal Coordinate Time (UTC) and, if DST is observed, the rules regarding the dates and times when DST starts and ends. Rules regarding DST dates are, for example, the first Sunday in November. DST rules, instead of explicit dates, make this product the natural choice for plugging into programs annually.

Because, TimeZoneInfo also covers known future changes to DST rules that are scheduled to occur, by including date with year ranges along with the Rules, this again makes TimeZoneInfo perfect for applications that are restricted from updates.

Introduction

Applications TimeZoneInfo is useful for determining the local time for any location in the World, whether on land or water. Coupled with the latitude/longitude coordinates of your geocoded business and customer information, you can use TimeZoneInfo for analysis of:

 marine and land-based sites  emerging markets  site location selection  telecommunications and worldwide network development  sales territory alignment  worldwide shipping and distribution  worldwide tracking  search and rescue missions  strategic military planning and command center operations  homeland security initiatives  communication control centers  … and more

TimeZoneInfo can help you make more informed business decisions, control costs, identify potential marketing opportunities, and enhance profitability.

In addition, TimeZoneInfo has been developed to compliment Stopwatch Data’s WorldMap product. Coupled together, these two products provide an unparalleled resource for global analysis.

Background and Reference Information

Data Source and Methodology The data in TimeZoneInfo is created from numerous resources researched by Stopwatch Data, LLC.

Mapped Geographies

The country map objects stem from Vector Map Level 0 and are constantly modified to reflect current country borders and their territorial waters. In addition, the country geographies and names have been updated to reflect the International Standards Organization (ISO) naming conventions and recognition of sovereign territories. The division of lands, islands, and waters into a timezone band have originally stemmed from the Central Intelligence Agency (CIA) publications. These allocations are updated by referencing atlases, and by contacting government agencies within individual countries.

Rules and Decrees

DST observed start/end times and dates, and DST rules stem from numerous sources including individual government web-sites and the examination of documented decrees set forth by each country.

Not all countries observe DST, and of the countries that do, some parts might be exempt from following DST. To add to the complexity, a few countries vary the length of DST observance from year to year, making the start and end dates unpredictable. It has happened where a country decreed to remain on DST for several years. Therefore, the rules that exist for applying DST cannot always predict when DST is actually observed.

National Sovereign Territory Countries bounded by water have sovereignty beyond the shore, known as territorial waters, or territorial sea. Territorial Waters is a belt of coastal waters extending twelve nautical miles (22 kilometers), (but can vary, at the coastal country's discretion) from the mean low water mark of a littoral state, or from internal waters, as per the 1982 United Nations Convention on the Law of the Sea. These territorial waters are regarded as the sovereign territory of the state (except that foreign ships, both military and civilian, are allowed innocent passage through it).

Regarding lakes and bays, a sovereign state has complete jurisdiction over internal waters, where not even innocent passage is allowed.

Background and Reference Information

Map Depiction of Territorial Waters TimeZoneInfo recognizes the need to honor time, based on the sovereign jurisdiction of nations. A 12 mile territorial boundary around coastal nations is depicted, and particularly important for marine operations upon waters.

Territorial and Internal Waters are more closely and legally defined by the statements below, followed with the rules applied by Stopwatch Data, to create and depict a sovereign state’s waters.

A) The mean low water mark may be an unlimited distance from permanently exposed land, provided that some portion of elevations exposed at low tide but covered at high tide (like mud flats) is within 12 nautical miles of permanently exposed land.

Stopwatch Data uses the costal mean low water mark as defined by VMAP0 data from National Geospatial-Intelligence Agency (NGA).

B) Completely enclosed seas, lakes, and rivers are considered internal waters.

These types of water areas are depicted as the sovereign territory of the bounding country.

C) Internal Waters constitute waters landward of lines connecting fringing islands along a coast or landward of lines across the mouths of rivers that flow into the sea.

These types of water areas are depicted as the sovereign territory of the bounding country.

D) Bays are defined as indentations between headlands having an area greater than that of a semicircle. If they do not exceed 24 nautical miles (44 km) between headlands then they are internal waters.

These types of water areas are depicted as the sovereign territory of the bounding country.

E) If a Bay’s entrance is wider than 24 nautical miles between the headlands, then that portion landward of a 24 nautical mile straight line that touches opposite low-water marks across the bay positioned to contain the greatest water area are internal waters.

This defined boundary is depicted as the sovereign territory of the bounding country.

F) All archipelagic waters within the outermost islands of an archipelagic state like Indonesia or the Philippines are also considered internal waters.

These types of water areas are depicted as the sovereign territory of the bounding country.

G) Other Rules

 The extension of the boundary at the coast, between two or more countries, is determined manually based on the following priority:

Background and Reference Information

 Internal Waters may be bordered by more than one nation. In the absence of a decree or law governing the border along the water, this water area is equally split based on area, shape, and existence of islands.

Frequency of Data Updates The data in the TimeZoneInfo product is continually updated, year-round. The product is released on a semi-annual basis to ensure that you receive the most up to date information possible.

Data Descriptions

Time Zones Table The Time Zones table contains the geographic boundaries for the time zones. The table has one or more records per country, each defining the geographic extent and UTC-offset of a time zone observed by that country. Coastal countries include territorial waters, which typically extends twelve miles from the shoreline. The table also includes boundaries for each of the twenty-five nautical time zones. Nautical time zones are named using a letter from A through Z, excluding the letter J.

When a change to the UTC-offset and/or boundary for a time zone is scheduled to occur at some future date, the table contains two records for that time zone – one for the current definition, and one representing time zone after the time change. The ValidFrom and ValidUntil fields indicate the effective period for each definition. The boundaries for these two definitions will typically overlap one another. However, the dates defined by ValidFrom and ValidUntil will not overlap, nor will there be any gap between the ranges. Thus, for any given date, there is only one valid time zone definition within the extents shared by the two boundaries.

The table is related to the DST Rules table (containing the start and end dates of DST observance) by the DSTRule field. This field contains a name uniquely identifying the records in the DST Rules table that define the DST rules for the time zone. If a time zone does not follow any DST rules, the DSTRule field is blank. Multiple time zone records can refer to the same DST Rules record. The DST Rules table contains multiple records for a named DSTRule if there are changes scheduled to occur in the future. The ValidFrom and ValidUntil fields in the DST Rules table indicate the effective period for each rule.

Table Format

MapInfo Table: TimeZones.tab (.dat, .id, and .map) ESRI Shapefile: TimeZones.shp (.dbf, .prj, and .shx)

Display Characteristics

Feature Description Graphic Object Details Time Zones Filled region with thin black border Pen (1,2,0) Brush - various

Table Structure

Field Type Size Description COUNTRY C 50 short name of country in English (ISO standard) ISO_2 C 2 two-character ISO code FIPS C 2 character code identifying the basic geopolitical entity (country code) as listed by the Federal Information Processing Standard (FIPS)

Data Descriptions

VALIDFROM C 10 the date, formatted as yyyy/mm/dd, when the boundary and/or attributes for the time zone became valid; if empty, there are no known time zone definitions that were valid prior to this one VALIDUNTIL C 10 the last date, formatted as yyyy/mm/dd, when the boundary and/or attributes for the time zone are still valid; if empty, there are no known changes to this time zone that are schedule to occur in the future TIMEZONE C 50 the names and abbreviations for the time zone STDOFFSET C 6 offset from UTC, formatted as [-]hh:mm; e.g., -1:30 for minus one hour and 30 minutes DSTRULE C 50 a named reference to the records in the DST Rules table containing the DST rules for the time zone; if empty, the time zone does not follow any DST rules ZoneName C 40 Time zone name as established by the Internet Assigned Numbers Authority (IANA); e.g., Europe/Madrid

Data Descriptions

DST Rules Table The DST Rules table contains information indicating when each time zone begins and ends observing DST. This table contains attribute information only and does not have any associated geography. Each record indicates when a time zone begins and ends observing DST. The dates are not specific to any one calendar year, but instead are represented as rules that can be used to derive the dates for any given year. A description of the rules can be found in the Date Rule Formats section after the table format.

When a change to the DST rules for a time zone is scheduled to occur at some future date, the table contains two records – one for the current rule, and one representing rules after the change. The ValidFrom and ValidUntil fields indicate the effective period for each rule record. The dates defined by ValidFrom and ValidUntil will not overlap, nor will there be any gap between the ranges. Thus, for any given date, there is only one valid rule for the time zone.

The table is related to the Time Zones table (which holds the geographic boundaries of countries cut by time zone) by the DSTRule field. This field contains a name that uniquely identifies records in the DST Rules table for the time zone. Multiple time zone records can refer to the same DST Rules records.

Table Format MapInfo Table: DSTRules.tab (.dat) ESRI Shapefile: DSTRules.shp (.dbf, and .shx)

Field Type Size Description DSTRULE C 50 Stopwatch Data assigned name for the rule; this name is unique for any given date when considered in conjunction with the ValidFrom and ValidUntil fields VALIDFROM C 10 the date, formatted as yyyy/mm/dd, when the DST rules became valid; if empty, there are no known DST rules that were valid prior to this one VALIDUNTIL C 10 the last date, formatted as yyyy/mm/dd, when the DST rules are still valid; if empty, there are no known changes to these rules that are schedule to occur in the future DSTOFFSET C 4 offset from standard time, formatted as h:mm; e.g., 0:30 for plus 30 minutes STARTFMT C 2 a number identifying the format used for the StartDate rule; see the Date Rule Formats below for details STARTDATE C 16 starting date for DST, formatted as a rule using the syntax identified by StartFmt STARTTIME C 5 starting time for DST specified as local military time, formatted as hh:mm ENDFMT C 2 a number identifying the format used for the EndDate rule; see the Date Rule Formats below for details ENDDATE C 16 ending date for DST, formatted as a rule using the syntax identified by EndFmt

Data Descriptions

ENDTIME C 5 ending time for DST specified as local military time, formatted as hh:mm

Date Rule Formats The StartDate and EndDate fields in the DST Rules table specify dates as a rule instead of using explicit dates. These rules are specified using one of three possible formats as defined in the following table. The format of the StartDate for a record is indicated by number in the StartFmt field, and EndFmt identifies the format of the EndDate.

Format Syntax Description 1 mo day mo the month; possible values are Jan, Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov, Dec day a numeric value representing the day of the month

Examples Feb 25 Oct 1

2 mo fl dow mo the month; possible values are Jan, Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov, Dec fl possible values are first or last dow the day of the week; possible values are Mon, Tue, Wed, Thu, Fri, Sat, Sun

Examples Mar last Thu (last Thursday in March) Nov first Sun (first Sunday in November)

3 mo dow op day mo the month; possible values are Jan, Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov, Dec dow the day of the week; possible values are Mon, Tue, Wed, Thu, Fri, Sat, Sun op one of >, >=, <=, or < day a numeric value representing the day of the month

Examples Apr Sun >= 1 (first Sunday in April) Oct Sun >= 15 (third Sunday in October)