Good news bad news: Beijing’s pollution hasn’t gotten worse over the last five years. But it’s also not getting any better, according to analysis of a five-year US Embassy data release by The Wall Street Journal.

That average reading of Particulate Matter (PM 2.5) for the total period from when data was first collected and released in 2008 until now is 100. That level is still four to six times higher than levels considered normal by organizations such as the US Environmental Protection Agency and the World Health Organization.

The worst hour during the five-plus year period was 11pm to midnight on Jan 23, 2012, which coincides with that year’s Spring Festival celebrations, and especially the accompanying fireworks. PM 2.5 readings spiked to 994. The worst day was Jan 12, 2013, when the 24-hour average reading was 569, the highest day on record so far.

Read the whole story here and see all of the Beijinger’s pollution coverage here.

Photo: Tom Arnstein