Question: According to the experts, what number of years did the High Renaissance occur?
About the article "High Renaissance", section "Overview".

Candidate passages:
Experts debate what changes need to occur in the legal process in response to research on inaccuracy of eyewitness testimony. 
In 2005, Renaissance Capital and FTSE Group launched the FTSE Renaissance IPO Index Series.
As the series expanded to encompass a growing number of developed and emerging markets, its name was changed to the FTSE Renaissance Global IPO Index Series.
According to a FTSE fact sheet, "Qualified IPOs are added to the indices at the end of their first trading day and removed after approximately two years, when they become seasoned equities."
Scholar F. O. Matthiessen originated the phrase "American Renaissance" in his 1941 book "American Renaissance: Art and Expression in the Age of Emerson and Whitman".
Although Mathiessen limited his definition to the period between 1850 and 1855, the term has since expanded to a broader range of time.
In "The American Renaissance Reconsidered", for example, Eric Sundquist expands the years covered by the American Renaissance to "the 1830s through the Civil War."
The notion of an American Renaissance has been criticized for overemphasizing a small number of white male writers and artifacts of high culture.
William E. Cain noted the "extreme white male formation" of Mathiessen's list of authors and stated that by "devoting hundreds of pages of analysis and celebration to five white male authors, Mathiessen unwittingly prefigured in his book what later readers would dispute and labor to correct."
The demographic exclusivity of the American Renaissance began eroding toward the end of the twentieth century.
Emily Dickinson, who began her poetry in the late 1850s, made her way into the canon.
Harriet Beecher Stowe’s "Uncle Tom’s Cabin" (1852) rose to prominence in the late 1970s.
African American literature gained increasing recognition.
The American Renaissance continues as a central term in American studies.
The American Renaissance was for long considered synonymous with American Romanticism and was closely associated with Transcendentalism.
Often considered a movement centered in New England, the American Renaissance was inspired in part by a new focus on humanism as a way to move from Calvinism.
The thematic center of the American Renaissance was what Matthiessen called the "devotion" of all five of his writers to "the possibilities of democracy."
He presented the American Renaissance texts as "literature for our democracy” and challenged the nation to repossess them. 
Experts disagree on the number and nature of tones in the various dialects of Lao.
According to some, most dialects of Lao and Isan have six tones, those of Luang Prabang have five.
Tones are determined as follows:A silent ຫ (/h/) placed before certain consonants will produce place the other proceeding consonant in the high class.
This can occur before the letters ງ /ŋ/, ຍ /ɲ/, ຣ /r/, and ວ /v/ and combined in special ligatures (considered separate letters) such as ຫຼ /l/, ໜ /n/, and ໝ /m/.
In addition to ອ່ (low tone) and ອ້ (falling tone), there also exists the rare ອ໊ (high) ອ໋ (rising) tone marks. 
 Early Renaissance painting Renaissance Italian Renaissance painting Northern European Renaissance painting Artists of the Tudor court High Renaissance painting Mannerism