One of the goals of the US Stocks Database and the UK Stocks Database is to eliminate the survivorship bias and the exchange bias that all other stock databases suffer from. Survivorship bias occurs when only stocks currently listed are included in a database and delisted stocks are excluded. Exchange bias occurs when historical data for stocks that were previously listed on another exchange or traded over-the-counter are excluded, providing an incomplete picture of the history of the company’s stock price.
This can also create a sector bias. If a sector tends to have stocks listed on a particular exchange or over-the-counter and those stocks are excluded, whole sectors may be excluded from the database. For example, most financial stocks listed over-the-counter until the 1970s. Any U.S. database which excludes over-the-counter stocks before the 1970s excludes banks and insurance companies. Although individual banks and insurance companies were small, at any given point in time over 1000 banks and insurance companies listed over-the-counter in the United States.
Exchange Bias in The Course of the Exchange
In the United Kingdom, the exchange bias occurs because databases focus on trading on the London Stock Exchange, but ignore trading in Scotland, Ireland or on provincial exchanges. This bias means that whole sectors of the British economy, such as canal stocks, may be excluded or have their role minimized. The London Stock Exchange was founded in 1801 and until then, no organized exchange existed in England. The Course of the Exchange recorded the prices of stocks and bonds traded in London in the 1700s, but included primarily the English Funds. Although canal stocks went through a bubble in the 1790s, they were completely ignored by The Course of the Exchange in the 1790s, leaving us with no record of the stocks’ behavior. Although The Course of the Exchange was the official source for trades on the London Stock Exchange, it was surprisingly selective. Each issue was two pages and focused on stocks trading in London. The Irish Funds were almost completely excluded from it. Scottish stocks received a special section in 1827, but this was removed in 1844 to make way for railroad stocks. Canal stocks were the largest sector in The Course of the Exchange in 1825 with over 70 canals listed, but had shrunk to 4 by 1864 when The Investor’s Monthly Manual listed almost 20. British mining stocks didn’t receive a special section until1857 even though local newspapers had tracked their behavior since the 1830s. Provincial shares were generally ignored unless the company grew large enough to be traded in London. Relying exclusively on The Course of the Exchange or The Times of London meant that many stocks traded in Britain, but not in London were often ignored. The United Kingdom suffered from exchange bias just as the United States suffered from exchange bias. The primary reason I can think of for this bias was the decision to keep The Course of the Exchange to one sheet, or two pages, in the 1840s. When the number of railroads, preferred stocks and bonds increased dramatically in the 1840s, the editors had to either expand to four pages, or reduce the number of non-railroad stocks that were covered. Unfortunately, they chose the latter. It wasn’t until 1864 when The Economist began publishing The Investor’s Monthly Manual that a single source covered all the shares that traded in London, the provinces, Scotland and Ireland. Before 1864, the only way to get a comprehensive overview of shares that traded in England was to go to provincial newspapers which provided data on the prices of locally traded stocks. A newspaper such as The Times of London was quite comprehensive in its coverage of stocks and bonds. Separate sections were provided for Railroads (British, Colonial and Foreign), Government Securities (English Funds, Colonial Securities, American Government Securities and Rails), Mines (British and Foreign), Joint Stock Banks, Docks and Miscellaneous Shares. Over 250 companies were listed in The Times or in The Course of the Exchange in 1864, but a closer analysis reveals how selective the choice of companies was. If you look at the Joint-Stock Banks section of either resource, you would think that a list of over 50 banks would cover the full gamut of banking throughout the British Isles, but you would be wrong. The list of joint-stock banks in The Times includes only London-based English banks and foreign banks that were listed on the London Stock Exchange. Very few provincial banks, and none from Ireland or Scotland, are listed.The Canal Bubble
Similarly, one of the most famous sectors of the British economy, canals, is entirely absent from The Times. The reason? Most canals were located in the Midlands of England and were relatively small in size. In the 1700s, the canals were traded locally and not in London where the English Funds dominated trading. Some canals had a very limited number of shares outstanding and were not liquid enough to trade in London. The Loughborough Canal, for example, only had 70 shares outstanding. Shareholders also rarely sold their canal shares. For the Leeds and Liverpool canal, built in 1789, 60% of the original shareholders still held their shares in 1795 and 46% in 1800. Some shares only became available because the owner died. Since there were no provincial stock exchanges, and the shares were rarely traded in London, how were canal shares bought and sold in the 1790s? As a review of provincial newspapers reveals, in the1790s, a local broker or shareholder placed an advertisement in the local newspaper announcing that he had shares available for purchase or that an auction of shares would be held on the morrow. Many of the ads provided information on recent dividends paid by the canal to entice bidders to purchase them, but unfortunately, the auctioneer never followed up the next day with an ad detailing what price the shares had sold for. Unfortunately, we may never be able to measure in detail the size of the canal bubble because there is almost no record of what price canal shares traded at in the 1790s. The table below shows the prices of shares of several canals from a Birmingham auction in 1792 and their price in 1812. Most of the shares were issued at £100, and by 1792 most were trading at a strong premium. However, what path the shares took between their issuance at £100, 1792 and 1812, we will probably never know.Canal | 1792 | 1812 |
Oxford | 75 | 645 |
Grand Junction | 472 | 200 |
Leicester | 340 | 215 |
Coventry | 450 | 855 |
Stourbridge | 450 | 190 |
Cromford | 189 | 270 |
Erewash | 674 | 603 |
Melton & Mowbray | 155 | 108.5 |
Trent & Mersey | 450 | 1200 |
The Irish Funds
In addition to the English Funds, there was also the Irish Funds. Ireland was in personal union with England in the 1700s, recognizing the king as sovereign, but maintaining a large degree of autonomy over local matters. After the French Invasion of Ireland in 1798 and the Irish rebellion of 1798, Britain determined to make Ireland a political part of Great Britain. In 1800, the Acts of Union created the United Kingdom of Great Britain and Ireland. Because the Acts of Union didn’t occur until 1800, Ireland issued its own debt, established the Bank of Ireland in 1783, the Grand Canal in 1756 and the Royal Canal in 1789. Consequently, we have a better picture the price behavior of Irish government debt, Bank of Ireland stock and Grand Canal shares than we do of shares issued in Scotland or in the provinces. Consequently, the Grand Canal and the Royal Canal are the only canal companies for which we have price data during the canal bubble. As the graph below shows, Grand Canal stock doubled in price in 1792, but declined in price thereafter.
Contrast this with the data we have on Scottish stocks. The Bank of Scotland was established in 1695, the Royal Bank of Scotland in 1727, and the British Linen Co. in 1746 but no data on their share prices exist until the 1820s. Scotland never issued debt separate from England so no Scottish Funds exists. Data on Scottish share prices before the 1820s is simply unavailable.