The estimated sign (also referred to as ‘e-mark’) is a mark that sometimes can be found on prepackages in Europe. The e-mark indicates that the prepackages are filled according to the European Directive 76/211/EEC.

The scope of the Directive is limited to prepackages that have a predetermined nominal quantity between 5 g or ml and 10 kg or l, are filled without the purchaser present and of which the quantity of product cannot be altered without opening or destroying the packing material.

The e-mark indicates that:

• the average
  Average
  In mathematics, an average, or central tendency of a data set is a measure of the "middle" value of the data set. Average is one form of central tendency. Not all central tendencies should be considered definitions of average....
  
   quantity of product in a batch of prepackages shall not be less than the nominal quantity stated on the label;
• the proportion of prepackages having a negative error greater than the tolerable negative error shall be sufficiently small for batches of prepackages to satisfy the requirements of the official reference test as specified in legislation;
• no prepackage having a negative error greater than twice the tolerable negative error may bear the estimated sign.

The tolerable negative error is related to the nominal quantity and varies between 9% on prepackages nominally 50 g or mL or less, to 1.5% on packages nominally 1 kg or L

Litre

pic|200px|right|thumb|One litre is equivalent to this cubeEach side is 10 cm1 litre water = 1 kilogram water The litre is a metric system unit of volume equal to 1 cubic decimetre , to 1,000 cubic centimetres , and to 1/1,000 cubic metre...

 or more. The tolerable error decreases as nominal quantity increases, and is done by alternating intervals where there is a fixed error (and thus over the interval the percentage error decreases) with intervals where there is a percentage error.

The estimated sign looks like a lower-case "e" and its shape is precisely defined by an EU directive. It must be placed in the same field of vison as the nominal quantity. This sign has been added to the Unicode

Unicode

Unicode is a computing industry standard for the consistent encoding, representation and handling of text expressed in most of the world's writing systems...

 list of characters, just as the symbol for the euro

Euro

The euro is the official currency of the eurozone: 17 of the 27 member states of the European Union. It is also the currency used by the Institutions of the European Union. The eurozone consists of Austria, Belgium, Cyprus, Estonia, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg,...

 has been, and can be considered a new basic character in a typeface

Typeface

In typography, a typeface is the artistic representation or interpretation of characters; it is the way the type looks. Each type is designed and there are thousands of different typefaces in existence, with new ones being developed constantly....

. It is character U+212E (℮).

The e-mark may be printed on prepackages if:

• the quantity of product in the prepackages and the labelling meet the requirements, and
• the packer that fills the prepackages carries out production checks in accordance with procedures recognized by the competent departments in the Member State, and
• if he holds at the disposal of those departments the documents containing the results of such checks

Tolerable Negative Error

Error tolerance decreases as nominal quantity increases, by alternating intervals of a given percent error with intervals of a given amount error: these interpolate between the stair-step decreases in percentage error.

Thus, for instance over the interval 50–100, the tolerable error is 4.5 g or ml. At the left end of the interval, this is 4.5/50 = 9% error (as with the interval 5–50), while at the right end of the interval, this is 4.5/100 = 4.5% error (as with the interval 100–200). The factor of 2 reduction in percentage tolerable error (9% to 4.5%) corresponds to the size of the interval (50–100).

Table of tolerable negative errors
Nominal quantity in g or ml	Tolerable negative error
5–50	9%
50–100	4.5 g or ml
100–200	4.5%
200–300	9 g or ml
300–500	3%
500–1000	15 g or ml
1000–10000	1.5%

In computer software

The "℮" symbol is listed in Unicode letterlike symbols

Letterlike Symbols

Letterlike Symbols are graphemes which are constructed mainly from the glyphs of one or more letters.In Unicode, Letterlike Symbols are placed in the block U+2100–214F, as in the following table.-See also:*Mapping of Unicode characters...

 and can be invoked in various operating systems as per the table below:

Apple Macintosh	in Character Palette, search for ESTIMATED SYMBOL
HTML or XML Extensible Markup Language Extensible Markup Language is a set of rules for encoding documents in machine-readable form. It is defined in the XML 1.0 Specification produced by the W3C, and several other related specifications, all gratis open standards....	℮ or ℮
Microsoft Windows Microsoft Windows Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...	Alt Alt key The Alt key on a computer keyboard is used to change the function of other pressed keys. Thus, the Alt key is a modifier key, used in a similar fashion to the Shift key. For example, simply pressing "A" will type the letter a, but if you hold down either Alt key while pressing A, the computer... + 212E or, using the Character Map Character Map Character Map is a utility included with Microsoft Windows operating systems and is used to view the characters in any installed font, to check what keyboard input is used to enter those characters, and to copy characters to the clipboard in lieu of typing them. The tool is usually useful for...  program, seach for estimated symbol.
Microsoft Word Microsoft Word Microsoft Word is a word processor designed by Microsoft. It was first released in 1983 under the name Multi-Tool Word for Xenix systems. Subsequent versions were later written for several other platforms including IBM PCs running DOS , the Apple Macintosh , the AT&T Unix PC , Atari ST , SCO UNIX,...	U+212e or, use Insert Symbol, choose "Letterlike Symbols": the '℮' symbol is near the end of the second row.
OpenOffice.org OpenOffice.org OpenOffice.org, commonly known as OOo or OpenOffice, is an open-source application suite whose main components are for word processing, spreadsheets, presentations, graphics, and databases. OpenOffice is available for a number of different computer operating systems, is distributed as free software...	In Special Characters, in first row of Letterlike Symbols
TeX TeX TeX is a typesetting system designed and mostly written by Donald Knuth and released in 1978. Within the typesetting system, its name is formatted as ....	\textestimated (requires the textcomp package)
Unicode Unicode Unicode is a computing industry standard for the consistent encoding, representation and handling of text expressed in most of the world's writing systems...	U+212e

Use of the sign

• Council Directive of 20 January 1976 on the approximation of the laws of the Member States relating to the making-up by weight or by volume of certain prepackaged products
• Nederlands Meetinstituut [NMi]
• WELMEC Working Group 6 on e-marked prepackages [WELMEC WG6]