literary-braille approach mentioned as an optional fallback. However, after trying the system out in the classroom, the dashes used in the numerals—as well as several other rows of special characters—were found to be too difficult to distinguish from dot-pairs, and thus the typical digraph-based numerals became the official standard in 1837. Implementation of UEB in English-speaking countries As of 2013, with the majority of English-speaking ICEB member-countries having officially adopted UEB, there remain barriers to implementation and deployment. Besides ICEB member-nations, there are also many other countries with blind citizens that teach and use English: India, Hong Kong/China, Pakistan, the Philippines, and so on. Many of these countries use non-UEB math notation, for English-speaking countries specifically, versions of the Nemeth Code were widespread by 1990 (in the United States, Western Samoa, Canada including Quebec, New Zealand, Israel, Greece, India, Pakistan, Sri Lanka, Thailand, Malaysia, Indonesia, Cambodia, Vietnam, and Lebanon) in contrast to the similar-to-UEB-but-not-identical Taylor notation in 1990 (used by the UK, Ireland, Australia, Nigeria, Hong Kong, Jordan, Kenya, Sierra Leone, Singapore, and Zimbabwe). Some countries in the Middle East used Nemeth and Taylor math-notations as of 1990, i.e. Iran and Saudi Arabia. As of 2013, it is unclear whether the English-using blind populations of various ICEB and non-ICEB nations will move to adopt the UEB, and if so, at what rate. Beyond official adoption rates in schools and by individuals, there are other difficulties. The vast majority of existing Braille materials, both printed and electronic, are in non-UEB encodings. Furthermore, other technologies that compete with braille are now ever-more-widely affordable (screen readers for electronic-text-to-speech, plus physical-pages-to-electronic-text software combined with high-resolution digital cameras and high-speed document scanners, and the increasing ubiquity of tablets/smartphones/PDAs/PCs). The percentage of blind children who are literate in braille is already declining—and even those who know some system tend not to know UEB, since that system is still very new. Still, as of 2012 many of the original goals for UEB have already been fully or partially accomplished: A unified literary code across most English-speaking countries (see separate section of this article on the adoption of UEB) Number of coding-subsystems reduced from five major and one minor ( + music/etc.) down to two major and two minor ( using formal codeswitching + music/ipa), plus the generality of the basic uebLiterary was increased to fully cover parentheses, math-symbols, emails, and websites. Reasonable level of backward compatibility with