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Re: Accessibility in Financial Tables in HTML

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From: Chagnon | PubCom.com
Date: Oct 13, 2015 2:21PM

Olaf D. wrote: "Each and every user will have to establish some context by reading the "stuff around the table".

Exactly. Otherwise the information, whether it's one cell or an entire paragraph, is out of context.

When we develop content, it's key for us to understand human behavior, perception, comprehension, and usability, as well as accessibility by different computer technologies. Leave out any part and your communication strategy fails.

There are better ways to provide the contextual information rather than through a Summary tag. (which can be debated in another post, but basically the summary tag isn't cross-media; that is, not all forms of content--PDF, Word, InDesign, PowerPoint, EPUB, HTML, etc.--can create and render the content consistently to ALL users across ALL media.)

Julie, in your table example, is it possible to reword and slightly re-structure the table so that it a) is more accessible to AT and b) is more easily comprehended by all users? Some techniques that might work for you:

1) Include prefatory information. This has been used by academia for umpteen decades and works very well to convey the overall "summary" of the table in a standard narrative <P> body text format. Short sentence or phrase; "X and Y, January – June 2015 in thousands of dollars (US). Right column shows percentage of change from previous year." Put the prefatory info right after the table title and before the actual table tag itself.

2) If a column/row is populated with dollar amounts, then have either the collar symbol "$" or the word "dollars" in the column header. Screen readers can voice the column headers as needed, and it reminds sighted users what's in the column, also. Everyone wins.

3) Regarding negative numbers, there isn't one way to designate them visually, and we also can't rely on how screen readers will voice them. They're all over the map.

This problem won't be fixed until WAI/WCAG figures out what's the best method and then sets it as the accessibility standard that will be followed by content creators and recognized by AT software. The choices (with a sample):
Parentheses (100)
Hyphen Unicode 002D -100
En-Dash Unicode 2013 –100
Minus symbol Unicode 2212 −100

From our testing across multiple media, the Unicode minus symbol is the most accurate solution, but it is unrecognized (or ignored) by most screen reader technologies. Hyphens and en-dashes are grammatically incorrect if used to designate negative numbers because that's not their grammatical purpose. I can't count how many times our blind accessibility testers didn't know that some numbers in a table were negative.

The majority of our language glyphs, punctuation, and mathematical symbols have been mapped to the Unicode character standard for a couple of decades. Why screen readers don't already recognize the basic Unicode character set and voice them by default is beyond my comprehension.

—BJC