Detailed Instructions: This task involves annotating the answer type to a given question that involve some kind of complex reasoning (including numerical reasoning). Note that the questions require looking at more than one part of the passage to answer. There are 3 possible answer types (i) spans, (ii) numbers and (iii) dates. If the answer can be found in the passage, label it as "span". If the answer is a number, label as "number". Similarly, label "date" if you think the answer to the given question is a date.
Q: Passage: By 2011 fewer than 7% of employees in the private sector belonged to unions. The UAW's numbers of automobile union members are representative of the manufacturing sector: 1,619,000 active members in 1970, 1,446,000 in 1980, 952,000 in 1990, 623,000 in 2004, and 377,000 in 2010 . By 2014, coal mining had largely shifted to open-pit mines in Wyoming, and there were only 60,000 active coal miners. The UMW has 35,000 members, of whom 20,000 were coal miners, chiefly in underground mines in Kentucky and West Virginia. By contrast it had 800,000 members in the late 1930s. However it remains responsible for pensions and medical benefits for 40,000 retired miners, and for 50,000 spouses and dependents.
Question: Which year had less than 900000 automobile union members but more than 400000?
A:
date