Overseas Travel and Tourism: Provisional Results for May 2015

1. The figures relate to the number of completed visits, not the number of visitors. Anyone entering or leaving more than once in the same period is counted on each visit. The count of visits relates to UK residents returning to this country and to overseas residents leaving it

2. Day-visits (that is trips that do not involve an overnight stay) abroad by UK residents as well as day trips to the UK by overseas residents are included in the figures for visits and expenditure. Please note they do not cover day visits to or from the Irish Republic across the land border, although they are included in total visits

3. An overseas visitor means a person who, being permanently resident in a country outside the United Kingdom, visits the UK for a period of less than 12 months. UK citizens resident overseas for 12 months or more coming home on leave are included in this category. Visits abroad are visits for a period of less than 12 months by people permanently resident in the UK (who may be of foreign nationality)

4. When a resident of the UK has visited more than one country the entire visit, expenditure and stay are allocated to the country stayed in for the longest time

5. Visits for miscellaneous purposes include those for study; to attend sporting events; for shopping; health; religious; or for other purposes; together with visits for more than one purpose when none predominates (for example visits both on business and on holiday). Overseas visitors staying overnight in the UK en route to other destinations are also included in miscellaneous purposes

6. Adjustments are made to the reported cost of an inclusive tour so that only the amount earned by the country of visit (for example accommodation costs, car hire, etc.) is included. This estimate is then added to an individual's spending to give the total spending in the country of visit (see also note 7)

7. Earnings and expenditure figures cover the same categories of travellers as do the number of visits, except that in addition the earnings figures include the expenditure by same day transit passengers , and the foreign exchange earnings and expenditure due to travel relating to the Channel Islands. They exclude payments for air, sea and rail travel to and from the UK. For any traveller on an inclusive tour an estimate of the return fare is deducted from the total tour price

8. Earnings do not include the personal export of cars that have been purchased in the United Kingdom by overseas residents. Similarly spending excludes the personal import of cars by UK residents

9. An estimate for purchases by overseas visitors at airport duty free shops is included in the figures for earnings. Such purchases on British carriers are still excluded

10. The question to identify whether the cost of fares and accommodation can be separated was simplified in the 2014 questionnaire. Up to December 2013 the question read: "Was your accommodation abroad paid for as part of an inclusive tour or holiday where fares and accommodation cannot be separated?" From January 2014 the question read: "Can you separate the cost of your fares and accommodation?" The routing to this question has remained constant and all respondents are routed to this question, regardless of purpose of visit. If they answer yes they are then asked to supply the breakdown of costs. Respondents whose purpose for visits was not "holiday" are still able to answer that they cannot separate fare and accommodation costs. This change should improve the cost breakdown of information collected

• North America:

  Canada (including Greenland and St Pierre et Miquelon), USA (including Puerto Rico and US Virgin Islands)

• Europe:

  All countries within the European Union (see below for listing) plus the following central and Eastern European countries: North Cyprus, Gibraltar, Iceland (including Faroe Islands), Norway, Switzerland (including Liechtenstein), Turkey, the former USSR and the states of former Yugoslavia

• EU15:

  All countries that joined the European Union before January 1 2004: Austria, Belgium, Denmark, France (including Monaco), Finland, Germany, Greece, Irish Republic, Italy (including San Marino and Vatican City), Luxembourg, Netherlands, Portugal (including Azores and Madeira), Spain (including Canary Islands, the Balearic Islands and Andorra) and Sweden. Note that the UK is among the 15 countries that formed the European Union prior to January 2004, but due to the nature of the data displayed in the IPS reference tables data for the UK is excluded

• European Union:

  All countries that are current members of the European Union: Austria, Belgium, Bulgaria, Croatia**, Cyprus*, Czech Republic, Denmark, Estonia, France (including Monaco), Finland, Germany, Greece, Hungary, Irish Republic, Italy (including San Marino and Vatican City), Latvia, Lithuania, Luxembourg, Malta, Netherlands, Poland, Portugal (including Azores and Madeira), Romania, Spain (including Canary Islands, the Balearic Islands and Andorra), Slovakia, Slovenia and Sweden. Note that the UK is a member of the European Union but due to the nature of the data displayed in the IPS reference tables data for the UK is excluded

• Other European Union:

  All countries that joined the European Union from 1 January 2004 onwards: Bulgaria, Croatia**, Cyprus*, Czech republic, Estonia, Hungary, Latvia, Lithuania, Malta, Poland, Romania, Slovakia and Slovenia

  *Only the south of Cyprus is a member of the EU but the IPS is unable to separate North and South Cyprus for the period before May 2004 and so all of Cyprus is included in the European Union section until May 2004. From May 2004, only southern Cyprus is included in the European Union figures

  **Croatia joined the European Union on 1 July 2013 and data relating to Croatia collected from that date onwards has been included in the "European Union", "Other EU" and "Europe" categories. Data relating to Croatia collected prior to 1 July 2013 is included in the "Europe" category only

1. Holiday: Holiday/pleasure, to play amateur sport, cruise

2. Business: Business

3. Visit friends or relatives: Visit family, visit friends

4. Miscellaneous: Other reasons or cases where the respondent is not able to give a single purpose as the main reason for visit

5. People migrating (to or from the UK) or travelling as crew of aircraft, ships or trains are excluded from analysis in this publication

1. The International Passenger Survey (IPS) produces estimates that are based on interviews with a stratified random sample of passengers entering and leaving the UK on the principle air, tunnel and sea routes. The main features of the stratification are: mode of transport (that is air, tunnel or sea), port and time of day.

2. The frequency of sampling within each stratum depends mainly on the variation of tourist expenditure and on the volume of migrants, for which the survey is also used to collect statistics. To collect overseas travel and tourism information, travellers passing through passport control are randomly selected for interview and in all some 281,000 interviews were conducted in 2014. Only interviews carried out at the end of a visit are used to generate estimates of expenditure and stay. Of these interviews around 44,000 provided the published information on foreign visitors to the UK and around 57,000 were used for the estimate of UK residents travelling abroad. The interviews were conducted on a purely voluntary and anonymous basis.

3. Despite the introduction in April 1999 of interviewing on air and sea routes to and from the Irish Republic the results from the IPS are still supplemented with estimates of travel between UK and the Irish Republic over the land border where no IPS interviewing takes place. Estimates for travel by land are based on information provided by the Central Statistics Office of the Irish Republic. Estimates of earnings and expenditure are also supplemented with figures from the Economic Advisor's Office of the States of Jersey, who provide information about the Channel Islands.

4. Over 95% of passengers entering and leaving the UK (excluding those travelling by land to and from the Irish Republic) travel on routes covered by the survey. The remainder are either passengers travelling at night when interviewing is suspended, or on those routes too small in volume to be covered. For those passengers, estimates are made and input into the main results of the survey.

5. At the major airports a sample of half days is taken and a fixed proportion of passengers are interviewed, whilst the smaller airports are sampled occasionally with the number of visits depending on the number of international passengers.

6. On the sea routes either particular cross-channel sailings are sampled and a fixed proportion of passengers interviewed on board, or a sample of days is taken and the passengers interviewed on the quay side.

7. In all, approximately 281,000 travellers were interviewed in 2014; the proportion varies from port to port.

8. UK residents who left a cuise boat at a foreign port and returned home on a scheduled air or sea service (for example, fly-cruises) are included in the IPS. Information on the number of passengers on cruises finishing in the UK is estimated in terms of the number of visits, length of stay and expenditure. These estimates are added to the cruise data collected from the IPS and included under the headings for "other areas", "holiday", and "sea". In 2010 a review took place of the methodology used to estimate the number of such visits. This review has led to more accurate methodology for estimating these visits and has resulted in an annual increase from the approximately 20,000 to 200,000 of such visits. The new estimates have been included since the publication Travel Trends 2010, published in late July 2011.

9. A complex weighting procedure is used in the survey results taking account of passengers movement statistics produced by the BAA plc and the Civil Aviation Authority for air traffic by the Department for Transport for sea traffic. For Heathrow, Gatwick and Manchester allowances are made for passengers in transit who do not pass through passport control and hence do not cross the IPS counting line.

10. For further information please read the IPS Methodology Report.

Figures for the most recent months are provisional and subject to revision in light of (a) more accurate data on passenger figures becoming available at the end of each quarter and (b) additional passenger data obtained at the end of each year.

IPS monthly estimates are revised in line with the IPS revisions policy . The revisions policy is available in the IPS Quality and Methodology Information (350.4 Kb Pdf) paper to assist users in the understanding of the cycle and frequency of data revisions. Users of this bulletin are strongly advised to read this policy before using this data for research or policy related purposes.

Planned revisions usually arise from either the receipt of revised passenger traffic data or the correction of errors to existing data identified later in the quarterly and annual processing cycle. Those of significant magnitude will be highlighted and explained.

Revisions to published monthly IPS estimates can be expected at the following times in the normal overseas travel and tourism publication schedule:

• monthly estimates for the current reference year will usually be revised and statisically benchmarked accross the quarter following the publication of the quarterly estimates within which that month falls

• monthly and quarterly estimates for the current reference year will be revised in the survey year’s annual data release (Travel Trends)

• monthly estimates, for the full calendar year, will be statistically benchmarked as part of the annual data processing and the monthly estimates for the year will then be replaced in the monthly release with the benchmarked estimate following publication of the annual report (Travel Trends)

All other revisions will be regarded as unplanned and will be dealt with by non-standard releases. All revisions will be released in compliance with the same principles as other new information. Please refer to the our guide to statistical revisions.

The main series are seasonally adjusted. This aids interpretation by identifying seasonal patterns and calendar effects and removing them from the unadjusted data. The resulting figures give a more accurate indication of underlying movements in the series.

The estimates produced from the IPS are subject to sampling errors that result because not every traveller to and from the UK is interviewed on the survey. Sampling errors are determined both by the sample design and by the sample size–generally speaking, the larger the sample supporting a particular estimate, the proportionately lower its sampling error. The survey sample size is approximately 25,000 per month. However, as the intensity of the sampling varies at each port, figures of a similar magnitude will not necessarily have the same percentage sampling error.

The IPS has a clustered sample design. The full effects of this complex sample design upon each of the main estimates is calculated, and it is calculated the 'complex' sampling errors which are quoted.

Accuracy of the estimates is expressed in terms of confidence intervals. The confidence interval is a range within which the true value of a proportion lies with known probability. For example, the 95% confidence interval represents the range into which there are 19 chances out of 20 that the true figure would fall had all passengers been sampled. This is obtained as +/- 1.96 the standard error.

Confidence intervals for quarterly and annual estimates are provided in the relevant overseas travel and tourism publications published by us.

One indication of the reliability of the key indicators in this release can be obtained by monitoring the size of revisions. Table 4 records the size and pattern of revisions to the quarterly IPS data which have occurred over the last 5 years to the following key seasonally adjusted estimates:

• the number of visits by overseas residents to the UK (GMAT)

• the number of visits abroad by UK residents (GMAX)

• earnings made from overseas residents in the UK (GMAZ)

• expenditure abroad by UK residents (GMBB)

Traffic at all airports and seaports is monitored regularly to assess if they should be included in the IPS sample. As a consequence Liverpool and Prestwick airports were introduced into the sample at the beginning of 2005. Between 2000 and 2004, traffic through Liverpool had quadrupled to "over 2 and a half million" international passengers, while at Prestwick there was a fivefold increase to nearly "1 and a half million" passengers over the same period. The inclusion of these ports in the IPS sample were shown to cause a discontinuity in regional results and methodology was modified to account for this. Similarly in early 2008, each of Doncaster, Bournemouth, Southampton and Heathrow Terminal 5 were added to the sample and in 2009 Aberdeen and Belfast International airports were added. Heathrow Terminal 2 was added to the sample from August 2014. Newhaven-Dieppe crossing was added to the sample from October 2014.

1. From January 2009, certain elements of the IPS have been revised to address recommendations put forward by the Interdepartmental Task Force on Migration Statistics, 2006. The changes involve revision to sample design, weighting and imputation methodology. These changes resulted in some discontinuity in estimates. An analysis was conducted and published in 2009. More details are available from the IPS team

2. The model used to produce seasonal adjustment estimates is reviewed approximately every 2 years. A review was conducted in late 2009 and the new model was used for the first time to produce the seasonally adjusted estimates used in the December 2009 statistical bulletin publication. Details of the seasonal adjustment model can be obtained from the IPS team using the contact details attached

Statistical series are affected by special events. However, as explained in our special events policy, it is not possible to make an estimate of the effect of particular events only on the basis of information collected in those series. However, we publish a special events calendar which may help the reader put some context on reported estimates.

IPS data files

IPS data for the years 1993 onwards are available online from www.ons.gov.uk. Travelpac is a free and simple to use dataset for those wishing to make further analyses of IPS data. It contains files provided in Excel and SPSS formats. More details can be found at Travelpac, 2014.

Monthly figures of overseas travel and tourism

These are published in the overseas travel and tourism statistical bulletin available from:

Office for National Statistics, Government Buildings, Cardiff Road, Newport, NP10 8XG.

Telephone: +44 (0)1633 455296 or from our website at www.ons.gov.uk.

Further statistics

More detailed statistics covering 1980 to 2014 may be found in the 2014 annual report, Travel Trends which is produced by us. A copy can be downloaded at Travel Trends, 2014.

Other analyses

For general questions about the IPS and requests for ad hoc data analysis (a service governed by our Income and Charging policy):

Telephone: +44 (0)1633 455678

Email: socialsurveys@ons.gov.uk

Notes for background notes: Further statistics and other analyses

1. The information provided to us by respondents is treated as strictly confidential as directed by the Code of Practice for Official Statistics. It is used to produce statistics that will not identify any individuals

2. A list of the job titles of those given pre-publication access to the contents of this statistical bulletin is available on the website

1. Details of the policy governing the release of new data are available by visiting www.statisticsauthority.gov.uk/assessment/code-of-practice/index.html or from the Media Relations Office email: media.relations@ons.gov.uk